Spotlight
A Way to Harvest Electricity from Trees

One freezing day in February 2006, physicist Andreas Mershin huddled with others around a tree on the Massachusetts Institute of Technology campus to watch an unlikely demonstration. An engineering company claimed it could produce electricity simply by wiring a nail in the tree’s trunk to a metal rod in the ground. Sure enough, the demo worked—but nobody knew exactly why.

Read More!

Inexpensive Thin Printable Batteries Developed

For a long time, batteries were bulky and heavy. Now, a new cutting-edge battery is revolutionizing the field. It is thinner than a millimeter, lighter than a gram, and can be produced cost-effectively through a printing process. Read more!

The Lilypad- A Water City

According to the less alarming forecasts of the GIEC, the ocean level should rise from 20 to 90 cm during the 21st Century with a status quo by 50 cm. As a solution to this alarming problem architect Vincent Callebaut came up with this ecotectural marvel. He called this project “Lilypad“, but this ecotectural marvel is also called as “Floating Ecopolis for Climate Refugees”.  Read more!

1,001 Cameras See In Gigapixels

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Recently, at Arizona State University’s Biodesign Institute, N.J. Tao and collaborators have found a way to make a key electronic component on a phenomenally tiny scale. Their single-molecule diode is described in this week’s online edition of Nature Chemistry.

This is a schematic for molecular diode. The symmetric molecule (top) allows for two-way current. The asymmetrical molecule (bottom) permits current in one direction only and acts as a single-molecule diode. (Credit: Biodesign Institute at Arizona State University)

This is a schematic for molecular diode. The symmetric molecule (top) allows for two-way current. The asymmetrical molecule (bottom) permits current in one direction only and acts as a single-molecule diode. (Credit: Biodesign Institute at Arizona State University)

In the electronics world, diodes are a versatile and ubiquitous component. Appearing in many shapes and sizes, they are used in an endless array of devices and are essential ingredients for the semiconductor industry. Making components including diodes smaller, cheaper, faster and more efficient has been the holy grail of an exploding electronics field, now probing the nanoscale realm.

Smaller size means cheaper cost and better performance for electronic devices. The first generation computer CPU used a few thousand transistors, Tao says noting the steep advance of silicon technology. “Now even simple, cheap computers use millions of transistors on a single chip.”

But lately, the task of miniaturization has gotten much harder, and the famous dictum known as Moore’s law—which states that the number of silicon-based transistors on a chip doubles every 18-24 months—will eventually reach its physical limits. “Transistor size is reaching a few tens of nanometers, only about 20 times larger than a molecule,” Tao says. “That’s one of the reasons people are excited about this idea of molecular electronics.”

Diodes are critical components for a broad array of applications, from power conversion equipment, to radios, logic gates, photodetectors and light-emitting devices. In each case, diodes are components that allow current to flow in one direction around an electrical circuit but not the other. For a molecule to perform this feat, Tao explains, it must be physically asymmetric, with one end capable of forming a covalent bond with the negatively charged anode and the other with the positive cathode terminal.

The new study compares a symmetric molecule with an asymmetric one, detailing the performance of each in terms of electron transport. “If you have a symmetric molecule, the current goes both ways, much like an ordinary resistor,” Tao observes. This is potentially useful, but the diode is a more important (and difficult) component to replicate (Fig 1).

The idea of surpassing silicon limits with a molecule-based electronic component has been around awhile. “Theoretical chemists Mark Ratner and Ari Aviram proposed the use of molecules for electronics like diodes back in 1974,” Tao says, adding “people around world have been trying to accomplish this for over 30 years.”

Most efforts to date have involved many molecules, Tao notes, referring to molecular thin films. Only very recently have serious attempts been made to surmount the obstacles to single-molecule designs. One of the challenges is to bridge a single molecule to at least two electrodes supplying current to it. Another challenge involves the proper orientation of the molecule in the device. “We are now able to do this—to build a single molecule device with a well defined orientation,” Tao says.

The technique developed by Tao’s group relies on a property known as AC modulation. “Basically, we apply a little periodically varying mechanical perturbation to the molecule. If there’s a molecule bridged across two electrodes, it responds in one way. If there’s no molecule, we can tell.”

The interdisciplinary project involved Professor Luping Yu, at the University of Chicago, who supplied the molecules for study, as well as theoretical collaborator, Professor Ivan Oleynik from the University of South Florida. The team used conjugated molecules, in which atoms are stuck together with alternating single and multiple bonds. Such molecules display large electrical conductivity and have asymmetrical ends capable of spontaneously forming covalent bonds with metal electrodes to create a closed circuit.

The project’s results raise the prospect of building single molecule diodes – the smallest devices one can ever build. “I think it’s exciting because we are able to look at a single molecule and play with it, ” Tao says. “We can apply a voltage, a mechanical force, or optical field, measure current and see the response. As quantum physics controls the behaviors of single molecules, this capability allows us to study properties distinct from those of conventional devices.”

Chemists, physicists, materials researchers, computational experts and engineers all play a central role in the emerging field of nanoelectronics, where a zoo of available molecules with different functions provide the raw material for innovation. Tao is also examining the mechanical properties of molecules, for example, their ability to oscillate. Binding properties between molecules make them attractive candidates for a new generation of chemical sensors. “Personally, I am interested in molecular electronics not because of their potential to duplicate today’s silicon applications, ” Tao says. Instead, molecular electronics will benefit from unique electronic, mechanical, optical and molecular binding properties that set them apart from conventional semiconductors. This may lead to applications complementing rather than replacing silicon devices.

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Recently, at Arizona State University’s Biodesign Institute, N.J. Tao and collaborators have found a way to make a key electronic component on a phenomenally tiny scale. Their single-molecule diode is described in this week’s online edition of Nature Chemistry.

This is a schematic for molecular diode. The symmetric molecule (top) allows for two-way current. The asymmetrical molecule (bottom) permits current in one direction only and acts as a single-molecule diode. (Credit: Biodesign Institute at Arizona State University)

This is a schematic for molecular diode. The symmetric molecule (top) allows for two-way current. The asymmetrical molecule (bottom) permits current in one direction only and acts as a single-molecule diode. (Credit: Biodesign Institute at Arizona State University)

In the electronics world, diodes are a versatile and ubiquitous component. Appearing in many shapes and sizes, they are used in an endless array of devices and are essential ingredients for the semiconductor industry. Making components including diodes smaller, cheaper, faster and more efficient has been the holy grail of an exploding electronics field, now probing the nanoscale realm.

Smaller size means cheaper cost and better performance for electronic devices. The first generation computer CPU used a few thousand transistors, Tao says noting the steep advance of silicon technology. “Now even simple, cheap computers use millions of transistors on a single chip.”

But lately, the task of miniaturization has gotten much harder, and the famous dictum known as Moore’s law—which states that the number of silicon-based transistors on a chip doubles every 18-24 months—will eventually reach its physical limits. “Transistor size is reaching a few tens of nanometers, only about 20 times larger than a molecule,” Tao says. “That’s one of the reasons people are excited about this idea of molecular electronics.”

Diodes are critical components for a broad array of applications, from power conversion equipment, to radios, logic gates, photodetectors and light-emitting devices. In each case, diodes are components that allow current to flow in one direction around an electrical circuit but not the other. For a molecule to perform this feat, Tao explains, it must be physically asymmetric, with one end capable of forming a covalent bond with the negatively charged anode and the other with the positive cathode terminal.

The new study compares a symmetric molecule with an asymmetric one, detailing the performance of each in terms of electron transport. “If you have a symmetric molecule, the current goes both ways, much like an ordinary resistor,” Tao observes. This is potentially useful, but the diode is a more important (and difficult) component to replicate (Fig 1).

The idea of surpassing silicon limits with a molecule-based electronic component has been around awhile. “Theoretical chemists Mark Ratner and Ari Aviram proposed the use of molecules for electronics like diodes back in 1974,” Tao says, adding “people around world have been trying to accomplish this for over 30 years.”

Most efforts to date have involved many molecules, Tao notes, referring to molecular thin films. Only very recently have serious attempts been made to surmount the obstacles to single-molecule designs. One of the challenges is to bridge a single molecule to at least two electrodes supplying current to it. Another challenge involves the proper orientation of the molecule in the device. “We are now able to do this—to build a single molecule device with a well defined orientation,” Tao says.

The technique developed by Tao’s group relies on a property known as AC modulation. “Basically, we apply a little periodically varying mechanical perturbation to the molecule. If there’s a molecule bridged across two electrodes, it responds in one way. If there’s no molecule, we can tell.”

The interdisciplinary project involved Professor Luping Yu, at the University of Chicago, who supplied the molecules for study, as well as theoretical collaborator, Professor Ivan Oleynik from the University of South Florida. The team used conjugated molecules, in which atoms are stuck together with alternating single and multiple bonds. Such molecules display large electrical conductivity and have asymmetrical ends capable of spontaneously forming covalent bonds with metal electrodes to create a closed circuit.

The project’s results raise the prospect of building single molecule diodes – the smallest devices one can ever build. “I think it’s exciting because we are able to look at a single molecule and play with it, ” Tao says. “We can apply a voltage, a mechanical force, or optical field, measure current and see the response. As quantum physics controls the behaviors of single molecules, this capability allows us to study properties distinct from those of conventional devices.”

Chemists, physicists, materials researchers, computational experts and engineers all play a central role in the emerging field of nanoelectronics, where a zoo of available molecules with different functions provide the raw material for innovation. Tao is also examining the mechanical properties of molecules, for example, their ability to oscillate. Binding properties between molecules make them attractive candidates for a new generation of chemical sensors. “Personally, I am interested in molecular electronics not because of their potential to duplicate today’s silicon applications, ” Tao says. Instead, molecular electronics will benefit from unique electronic, mechanical, optical and molecular binding properties that set them apart from conventional semiconductors. This may lead to applications complementing rather than replacing silicon devices.

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A magnetic charge can behave and interact just like an electric charge in some materials, according to new research led by the London Centre for Nanotechnology (LCN).

The magnetic equivalent of electricity in a spin ice material: atom sized north and south poles in spin ice drift in opposite directions when a magnetic field is applied.

The magnetic equivalent of electricity in a 'spin ice' material: atom sized north and south poles in spin ice drift in opposite directions when a magnetic field is applied.

The findings could lead to a reassessment of current magnetism theories, as well as significant technological advances.

The research, published in Nature, proves the existence of atom-sized ‘magnetic charges’ that behave and interact just like more familiar electric charges. It also demonstrates a perfect symmetry between electricity and magnetism – a phenomenon dubbed ‘magnetricity’ by the authors from the LCN and the Science and Technology Facility Council’s ISIS Neutron and Muon Source.

In order to prove experimentally the existence of magnetic current for the first time, the team mapped Onsager’s 1934 theory of the movement of ions in water onto magnetic currents in a material called spin ice. They then tested the theory by applying a magnetic field to a spin ice sample at a very low temperature and observing the process using muons at ISIS.

The experiment allowed the team to detect magnetic charges in the spin ice (Dy2Ti2O7), to measure their currents, and to determine the elementary unit of the magnetic charge in the material. The monopoles they observed arise as disturbances of the magnetic state of the spin ice, and can exist only inside the material.

Professor Steve Bramwell, LCN co-author of the paper, said: “Magnetic monopoles were first predicted to exist in 1931, but despite many searches, they have never yet been observed as freely roaming elementary particles. These monopoles do at least exist within the spin ice sample, but not outside.

“It is not often in the field of physics you get the chance to ask ‘How do you measure something?’ and then go on to prove a theory unequivocally. This is a very important step to establish that magnetic charge can flow like electric charge. It is in the early stages, but who knows what the applications of magnetricity could be in 100 years time.”

Professor Keith Mason, Chief Executive of STFC said: “The unequivocal proof that magnetic charge is conducted in spin ice adds significantly to our understanding of electromagnetism. Whilst we will have to wait to see what applications magnetricity will find in technology, this research shows that curiosity driven research will always have the potential to make an impact on the way we live and work. Advanced materials research depends greatly on having access to central research labs like ISIS allowing the UK science community to flourish and make exciting discoveries like this.”

Dr Sean Giblin, instrument scientist at ISIS and co-author of the paper, added: “The results were astounding, using muons at ISIS we are finally able to confirm that magnetic charge really is conducted through certain materials at certain temperatures – just like the way ions conduct electricity in water.”

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A magnetic charge can behave and interact just like an electric charge in some materials, according to new research led by the London Centre for Nanotechnology (LCN).

The magnetic equivalent of electricity in a spin ice material: atom sized north and south poles in spin ice drift in opposite directions when a magnetic field is applied.

The magnetic equivalent of electricity in a 'spin ice' material: atom sized north and south poles in spin ice drift in opposite directions when a magnetic field is applied.

The findings could lead to a reassessment of current magnetism theories, as well as significant technological advances.

The research, published in Nature, proves the existence of atom-sized ‘magnetic charges’ that behave and interact just like more familiar electric charges. It also demonstrates a perfect symmetry between electricity and magnetism – a phenomenon dubbed ‘magnetricity’ by the authors from the LCN and the Science and Technology Facility Council’s ISIS Neutron and Muon Source.

In order to prove experimentally the existence of magnetic current for the first time, the team mapped Onsager’s 1934 theory of the movement of ions in water onto magnetic currents in a material called spin ice. They then tested the theory by applying a magnetic field to a spin ice sample at a very low temperature and observing the process using muons at ISIS.

The experiment allowed the team to detect magnetic charges in the spin ice (Dy2Ti2O7), to measure their currents, and to determine the elementary unit of the magnetic charge in the material. The monopoles they observed arise as disturbances of the magnetic state of the spin ice, and can exist only inside the material.

Professor Steve Bramwell, LCN co-author of the paper, said: “Magnetic monopoles were first predicted to exist in 1931, but despite many searches, they have never yet been observed as freely roaming elementary particles. These monopoles do at least exist within the spin ice sample, but not outside.

“It is not often in the field of physics you get the chance to ask ‘How do you measure something?’ and then go on to prove a theory unequivocally. This is a very important step to establish that magnetic charge can flow like electric charge. It is in the early stages, but who knows what the applications of magnetricity could be in 100 years time.”

Professor Keith Mason, Chief Executive of STFC said: “The unequivocal proof that magnetic charge is conducted in spin ice adds significantly to our understanding of electromagnetism. Whilst we will have to wait to see what applications magnetricity will find in technology, this research shows that curiosity driven research will always have the potential to make an impact on the way we live and work. Advanced materials research depends greatly on having access to central research labs like ISIS allowing the UK science community to flourish and make exciting discoveries like this.”

Dr Sean Giblin, instrument scientist at ISIS and co-author of the paper, added: “The results were astounding, using muons at ISIS we are finally able to confirm that magnetic charge really is conducted through certain materials at certain temperatures – just like the way ions conduct electricity in water.”

Start uga_filter:

Rutgers researchers have discovered novel electronic properties in two-dimensional sheets of carbon atoms called graphene that could one day be the heart of speedy and powerful electronic devices.

Graphene sample with electrodes, fabricated using electron beam lithography

Graphene sample with electrodes, fabricated using electron beam lithography

The new findings, previously considered possible by physicists but only now being seen in the laboratory, show that electrons in graphene can interact strongly with each other. The behavior is similar to superconductivity observed in some metals and complex materials, marked by the flow of electric current with no resistance and other unusual but potentially useful properties. In graphene, this behavior results in a new liquid-like phase of matter consisting of fractionally charged quasi-particles, in which charge is transported with no dissipation.

In a paper issued online by the journal Nature and slated for print publication in the coming weeks, physics professor Eva Andrei and her Rutgers colleagues note that the strong interaction between electrons, also called correlated behavior, had not been observed in graphene in spite of many attempts to coax it out. This led some scientists to question whether correlated behavior could even be possible in graphene, where the electrons are massless (ultra-relativistic) particles like photons and neutrinos. In most materials, electrons are particles that have mass.

“Our work demonstrated that earlier failures to observe correlated behavior were not due to the physical nature of graphene,” said Eva Andrei, physics professor in the Rutgers School of Arts and Sciences. “Rather, it was because of interference from the material which supported graphene samples and the type of electrical probes used to study it.”

This finding should encourage scientists to further pursue graphene and related materials for future electronic applications, including replacements for today’s silicon-based semiconductor materials. Industry experts expect silicon technology to reach fundamental performance limits in a little more than a decade.

The Rutgers physicists further describe how they observed the collective behavior of the ultra-relativistic charge carriers in graphene through a phenomenon known as the fractional quantum Hall effect (FQHE). The FQHE is seen when charge carriers are confined to moving in a two-dimensional plane and are subject to a perpendicular magnetic field. When interactions between these charge carriers are sufficiently strong they form new quasi-particles with a fraction of an electron’s elementary charge. The FHQE is the quintessential signature of strongly correlated behavior among charge-carrying particles in two dimensions.

The FHQE is known to exist in semiconductor-based, two-dimensional electron systems, where the electrons are massive particles that obey conventional dynamics versus the relativistic dynamics of massless particles. However, it was not obvious until now that ultra-relativistic electrons in graphene would be capable of exhibiting collective phenomena that give rise to the FHQE. The Rutgers physicists were surprised that the FHQE in graphene is even more robust than in standard semiconductors.

Scientists make graphene patches by rubbing graphite – the same material in ordinary pencil lead – onto a silicon wafer, which is a thin slice of silicon crystal used to make computer chips. Then they run electrical pathways to the graphene patches using ordinary integrated circuit fabrication techniques. While scientists were able to investigate many properties of the resulting graphene electronic device, they were not able to induce the sought-after fractional quantum Hall effect.

Andrei and her group proposed that impurities or irregularities in the thin layer of silicon dioxide underlying the graphene were preventing the scientists from achieving the exacting conditions they needed. Postdoctoral fellow Xu Du and undergraduate student Anthony Barker were able to show that etching out several layers of silicon dioxide below the graphene patches essentially leaves an intact graphene strip suspended in mid-air by the electrodes. This enabled the group to demonstrate that the carriers in suspended graphene essentially propagate ballistically without scattering from impurities. Another crucial step was to design and fabricate a probe geometry that did not interfere with measurements as Andrei suspected earlier ones were doing. These proved decisive steps to observing the correlated behavior in graphene.

In the past few months, other academic and corporate research groups have reported streamlined graphene production techniques, which will propel further research and potential applications.

Andrei’s collaborators were Xu Du, now on faculty at Stony Brook University; Ivan Skachko, a post-doctoral fellow; Fabian Duerr, a master’s student; and Adina Luican, a doctoral student. The research was supported by the Department of Energy, the National Science Foundation, the Institute for Complex Adaptive Matter and Alcatel-Lucent.

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Rutgers researchers have discovered novel electronic properties in two-dimensional sheets of carbon atoms called graphene that could one day be the heart of speedy and powerful electronic devices.

Graphene sample with electrodes, fabricated using electron beam lithography

Graphene sample with electrodes, fabricated using electron beam lithography

The new findings, previously considered possible by physicists but only now being seen in the laboratory, show that electrons in graphene can interact strongly with each other. The behavior is similar to superconductivity observed in some metals and complex materials, marked by the flow of electric current with no resistance and other unusual but potentially useful properties. In graphene, this behavior results in a new liquid-like phase of matter consisting of fractionally charged quasi-particles, in which charge is transported with no dissipation.

In a paper issued online by the journal Nature and slated for print publication in the coming weeks, physics professor Eva Andrei and her Rutgers colleagues note that the strong interaction between electrons, also called correlated behavior, had not been observed in graphene in spite of many attempts to coax it out. This led some scientists to question whether correlated behavior could even be possible in graphene, where the electrons are massless (ultra-relativistic) particles like photons and neutrinos. In most materials, electrons are particles that have mass.

“Our work demonstrated that earlier failures to observe correlated behavior were not due to the physical nature of graphene,” said Eva Andrei, physics professor in the Rutgers School of Arts and Sciences. “Rather, it was because of interference from the material which supported graphene samples and the type of electrical probes used to study it.”

This finding should encourage scientists to further pursue graphene and related materials for future electronic applications, including replacements for today’s silicon-based semiconductor materials. Industry experts expect silicon technology to reach fundamental performance limits in a little more than a decade.

The Rutgers physicists further describe how they observed the collective behavior of the ultra-relativistic charge carriers in graphene through a phenomenon known as the fractional quantum Hall effect (FQHE). The FQHE is seen when charge carriers are confined to moving in a two-dimensional plane and are subject to a perpendicular magnetic field. When interactions between these charge carriers are sufficiently strong they form new quasi-particles with a fraction of an electron’s elementary charge. The FHQE is the quintessential signature of strongly correlated behavior among charge-carrying particles in two dimensions.

The FHQE is known to exist in semiconductor-based, two-dimensional electron systems, where the electrons are massive particles that obey conventional dynamics versus the relativistic dynamics of massless particles. However, it was not obvious until now that ultra-relativistic electrons in graphene would be capable of exhibiting collective phenomena that give rise to the FHQE. The Rutgers physicists were surprised that the FHQE in graphene is even more robust than in standard semiconductors.

Scientists make graphene patches by rubbing graphite – the same material in ordinary pencil lead – onto a silicon wafer, which is a thin slice of silicon crystal used to make computer chips. Then they run electrical pathways to the graphene patches using ordinary integrated circuit fabrication techniques. While scientists were able to investigate many properties of the resulting graphene electronic device, they were not able to induce the sought-after fractional quantum Hall effect.

Andrei and her group proposed that impurities or irregularities in the thin layer of silicon dioxide underlying the graphene were preventing the scientists from achieving the exacting conditions they needed. Postdoctoral fellow Xu Du and undergraduate student Anthony Barker were able to show that etching out several layers of silicon dioxide below the graphene patches essentially leaves an intact graphene strip suspended in mid-air by the electrodes. This enabled the group to demonstrate that the carriers in suspended graphene essentially propagate ballistically without scattering from impurities. Another crucial step was to design and fabricate a probe geometry that did not interfere with measurements as Andrei suspected earlier ones were doing. These proved decisive steps to observing the correlated behavior in graphene.

In the past few months, other academic and corporate research groups have reported streamlined graphene production techniques, which will propel further research and potential applications.

Andrei’s collaborators were Xu Du, now on faculty at Stony Brook University; Ivan Skachko, a post-doctoral fellow; Fabian Duerr, a master’s student; and Adina Luican, a doctoral student. The research was supported by the Department of Energy, the National Science Foundation, the Institute for Complex Adaptive Matter and Alcatel-Lucent.

Start uga_filter:

New research, released by the Catlin Arctic Survey and WWF, provides further evidence that the Arctic Ocean sea ice is thinning, supporting the emerging thinking that the Ocean will be largely ice-free during summer within a decade.

The Arctic Ocean sea ice is thinning, new data show, supporting the emerging thinking that the Ocean will be largely ice-free during summer within a decade.

The Arctic Ocean sea ice is thinning, new data show, supporting the emerging thinking that the Ocean will be largely ice-free during summer within a decade.

The Catlin Arctic Survey, completed earlier this year, provides the latest ice thickness record, drawn from the only survey capturing surface measurements conducted during winter and spring 2009.

The data (1), collected by manual drilling and observations on a 450-kilometre route across the northern part of the Beaufort Sea (2), suggests the survey area is comprised almost exclusively of first-year ice.

This is a significant finding because the region has traditionally contained older, thicker multi-year ice. The average thickness of the ice-floes measured 1.8 metres, a depth considered too thin to survive the next summer’s ice melt. (4)

These findings have been analysed by the Polar Ocean Physics Group (3) at the University of Cambridge, led by Professor Peter Wadhams, one of the world’s leading experts on sea ice cover in the North Pole region.

“With a larger part of the region now first year ice, it is clearly more vulnerable,” said Professor Wadhams. “The area is now more likely to become open water each summer, bringing forward the potential date when the summer sea ice will be completely gone.”

Wadhams continued: “The Catlin Arctic Survey data supports the new consensus view — based on seasonal variation of ice extent and thickness, changes in temperatures, winds and especially ice composition — that the Arctic will be ice-free in summer within about 20 years, and that much of the decrease will be happening within 10 years.”

“That means you’ll be able to treat the Arctic as if it were essentially an open sea in the summer and have transport across the Arctic Ocean.”

According to the scientists who have studied the data, the technique used by the explorers to take measurements on the surface of the ice has the potential to help ice modellers to refine predictions about the future survival or decline of the ice.

Catlin Arctic Survey expedition leader Pen Hadow commented: “This is the kind of scientific work we always wanted to support by getting to places in the Arctic which are otherwise nearly impossible to reach for research purposes. It’s what modern exploration should be doing. Our on-the-ice techniques are helping scientists to understand better what is going on in this fragile ecosystem.”

At the unveiling of the results in London, Dr. Martin Sommerkorn from WWF International Arctic Programme, which partnered with the Survey, said: “The Arctic sea ice holds a central position in our Earth’s climate system. Take it out of the equation and we are left with a dramatically warmer world.”

“Such a loss of Arctic sea ice cover has recently been assessed (5) to set in motion powerful climate feedbacks which will have an impact far beyond the Arctic itself – self perpetuating cycles, amplifying and accelerating the consequences of global warming. This could lead to flooding affecting one-quarter of the world’s population, substantial increases in greenhouse gas emissions from massive carbon pools and extreme global weather changes” Dr. Sommerkorn said.

“Today’s findings provide yet another urgent call for action to world leaders ahead of the UN climate summit in Copenhagen this December to rapidly and effectively curb global greenhouse gas emissions, with rich countries committing to reduce emissions by 40% by 2020.”

Notes:

  1. More than 6,000 measurements and observations from the expedition were used in the analysis. (“Verification of Catlin Arctic Survey Surface Observation Techniques, N. P. Toberg, P. Wadhams, Polar Ocean Physics Group, Department of Applied Mathematics and Theoretical Physics, University of Cambridge, October 2009)
  2. The survey began on March 1st 2009 at 81.83ºN 129.97ºW and ended after 73 days on May 7th at 85.45ºN 124.84ºW.
  3. The Polar Ocean Physics Group is part of the Department of Applied Mathematics and Theoretical Physics, University of Cambridge.
  4. The average (mean) thickness of the total ice cover when incorporating the rougher, compressed ridges of ice increased to 4.8m. Pressure ridges contain a large amount of ice below the surface.
  5. Reduced ice cover will lead to more greenhouse gases being released from the vast store of carbon currently locked in the frozen Arctic region. Arctic permafrost soils store twice as much carbon as in the atmosphere, and there is more carbon stored as methane hydrates in the frozen arctic seafloors than in all of Earth’s proven reserves of coal, oil and natural gas combined. The warming of the Arctic Ocean surface waters, resulting from more sea ice loss, will accelerate melting of the Greenland Ice Sheet, speeding up global sea level rise. Patterns of northern hemisphere ocean and weather will change, affecting access to natural resources, and food production.
Start uga_in_feed Ending uga_in_feed: Start uga_track_user Start uga_get_option: ignore_users uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: ignore_users (1) Start uga_get_option: max_user_level uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: max_user_level (8) Tracking user with level 0 Ending uga_track_user: 1 Calling preg_replace_callback: ]*?)href\s*=\s*['"](.*?)['"]([^>]*)>(.*?) Ending uga_filter:

New research, released by the Catlin Arctic Survey and WWF, provides further evidence that the Arctic Ocean sea ice is thinning, supporting the emerging thinking that the Ocean will be largely ice-free during summer within a decade.

The Arctic Ocean sea ice is thinning, new data show, supporting the emerging thinking that the Ocean will be largely ice-free during summer within a decade.

The Arctic Ocean sea ice is thinning, new data show, supporting the emerging thinking that the Ocean will be largely ice-free during summer within a decade.

The Catlin Arctic Survey, completed earlier this year, provides the latest ice thickness record, drawn from the only survey capturing surface measurements conducted during winter and spring 2009.

The data (1), collected by manual drilling and observations on a 450-kilometre route across the northern part of the Beaufort Sea (2), suggests the survey area is comprised almost exclusively of first-year ice.

This is a significant finding because the region has traditionally contained older, thicker multi-year ice. The average thickness of the ice-floes measured 1.8 metres, a depth considered too thin to survive the next summer’s ice melt. (4)

These findings have been analysed by the Polar Ocean Physics Group (3) at the University of Cambridge, led by Professor Peter Wadhams, one of the world’s leading experts on sea ice cover in the North Pole region.

“With a larger part of the region now first year ice, it is clearly more vulnerable,” said Professor Wadhams. “The area is now more likely to become open water each summer, bringing forward the potential date when the summer sea ice will be completely gone.”

Wadhams continued: “The Catlin Arctic Survey data supports the new consensus view — based on seasonal variation of ice extent and thickness, changes in temperatures, winds and especially ice composition — that the Arctic will be ice-free in summer within about 20 years, and that much of the decrease will be happening within 10 years.”

“That means you’ll be able to treat the Arctic as if it were essentially an open sea in the summer and have transport across the Arctic Ocean.”

According to the scientists who have studied the data, the technique used by the explorers to take measurements on the surface of the ice has the potential to help ice modellers to refine predictions about the future survival or decline of the ice.

Catlin Arctic Survey expedition leader Pen Hadow commented: “This is the kind of scientific work we always wanted to support by getting to places in the Arctic which are otherwise nearly impossible to reach for research purposes. It’s what modern exploration should be doing. Our on-the-ice techniques are helping scientists to understand better what is going on in this fragile ecosystem.”

At the unveiling of the results in London, Dr. Martin Sommerkorn from WWF International Arctic Programme, which partnered with the Survey, said: “The Arctic sea ice holds a central position in our Earth’s climate system. Take it out of the equation and we are left with a dramatically warmer world.”

“Such a loss of Arctic sea ice cover has recently been assessed (5) to set in motion powerful climate feedbacks which will have an impact far beyond the Arctic itself – self perpetuating cycles, amplifying and accelerating the consequences of global warming. This could lead to flooding affecting one-quarter of the world’s population, substantial increases in greenhouse gas emissions from massive carbon pools and extreme global weather changes” Dr. Sommerkorn said.

“Today’s findings provide yet another urgent call for action to world leaders ahead of the UN climate summit in Copenhagen this December to rapidly and effectively curb global greenhouse gas emissions, with rich countries committing to reduce emissions by 40% by 2020.”

Notes:

  1. More than 6,000 measurements and observations from the expedition were used in the analysis. (“Verification of Catlin Arctic Survey Surface Observation Techniques, N. P. Toberg, P. Wadhams, Polar Ocean Physics Group, Department of Applied Mathematics and Theoretical Physics, University of Cambridge, October 2009)
  2. The survey began on March 1st 2009 at 81.83ºN 129.97ºW and ended after 73 days on May 7th at 85.45ºN 124.84ºW.
  3. The Polar Ocean Physics Group is part of the Department of Applied Mathematics and Theoretical Physics, University of Cambridge.
  4. The average (mean) thickness of the total ice cover when incorporating the rougher, compressed ridges of ice increased to 4.8m. Pressure ridges contain a large amount of ice below the surface.
  5. Reduced ice cover will lead to more greenhouse gases being released from the vast store of carbon currently locked in the frozen Arctic region. Arctic permafrost soils store twice as much carbon as in the atmosphere, and there is more carbon stored as methane hydrates in the frozen arctic seafloors than in all of Earth’s proven reserves of coal, oil and natural gas combined. The warming of the Arctic Ocean surface waters, resulting from more sea ice loss, will accelerate melting of the Greenland Ice Sheet, speeding up global sea level rise. Patterns of northern hemisphere ocean and weather will change, affecting access to natural resources, and food production.
Start uga_filter:

Within the Consolider HOPE project (projects funded by the Ministry of Innovation and Science), a group of scientists at Universidad Pablo de Olavide (UPO), headed by Juan Antonio Anta, are working on the optimisation of a type of photovoltaic cell (Grätzel cell) that artificially mimics photosynthesis.

Grätzel cells are photovoltaic devices that take advantage of the interaction of a structured semiconductor less than nanometre in size and an organic dye that acts as a solar collector.

According to Elena Guillén, member of UPO’s Coloides y Celdas Solares Nanoestructuradas (Nanostructured Colloids and Solar Cells) Group, this dye can be either synthetic or natural and can even enable the use of chlorophyll for this type of cell.

Thus, researchers at UPO have begun a study with which they hope to increase the efficiency of these eosin or mercurochrome -based organic components by incorporating ionic salts, known as green solvents, with a view to preventing evaporation of the liquid compounds and the consequent reduction in efficiency.

Previous studies show that ionic salts are less volatile and it is this characteristic that the group headed by Professor Anta seeks to exploit. “Notwithstanding its liquid state, these types of solvents have high viscosity levels and, therefore, during the coming months we will continue our study, working on different alternatives within ionic liquids, their synthesis, etc.,” comments Elena Guillén.

The pros and cons of the new generation

Although there are already some third generation cells on the market (for example, for recharging mobile phones), according to the researchers their practical use is anecdotal. However, due to their properties of flexibility and variety of colours and shapes, the future of these cells lies in new market niches such as decoration or use in coloured windows that not only allow light through but use this light to generate electricity.

On the other hand, apart from the rapid amortisation of energy production costs -estimated in one year’s use-, there is also the low cost of the materials. “Organic materials are usually cheaper,” affirms the researcher, despite which the search continues for an alternative organic dye to the one currently used, derived from ruthenium.

“The paradox lies in the fact that if one uses these cells because their competitive edge is that they are cheaper and more readily available, and then one uses a dye based on a precious metal, what is the advantage?” points out Elena Guillén.

On the other hand, the researchers are aware that it is a relatively new technology -this type of cell was invented in 1991- that still need to be greatly developed. Furthermore, the maximum efficiency obtained in laboratory is only 11%, which is competitive but it drops when extrapolated to an industrial scale.

The main technological challenge is currently the problem of cell degradation. “If you use an organic dye, it can be degraded by the action of sunlight, with the consequent reduction in useful life compared to silicon cells. On the other hand,” the researcher highlights, “our group is working on one of the key aspect for improving cell stability – elimination of the need to use liquids that can present problems with evaporation, etc. and for which, as already mentioned, our focus is on the use of ionic salts.”

Start uga_in_feed Ending uga_in_feed: Start uga_track_user Start uga_get_option: ignore_users uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: ignore_users (1) Start uga_get_option: max_user_level uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: max_user_level (8) Tracking user with level 0 Ending uga_track_user: 1 Calling preg_replace_callback: ]*?)href\s*=\s*['"](.*?)['"]([^>]*)>(.*?) Ending uga_filter:

Within the Consolider HOPE project (projects funded by the Ministry of Innovation and Science), a group of scientists at Universidad Pablo de Olavide (UPO), headed by Juan Antonio Anta, are working on the optimisation of a type of photovoltaic cell (Grätzel cell) that artificially mimics photosynthesis.

Grätzel cells are photovoltaic devices that take advantage of the interaction of a structured semiconductor less than nanometre in size and an organic dye that acts as a solar collector.

According to Elena Guillén, member of UPO’s Coloides y Celdas Solares Nanoestructuradas (Nanostructured Colloids and Solar Cells) Group, this dye can be either synthetic or natural and can even enable the use of chlorophyll for this type of cell.

Thus, researchers at UPO have begun a study with which they hope to increase the efficiency of these eosin or mercurochrome -based organic components by incorporating ionic salts, known as green solvents, with a view to preventing evaporation of the liquid compounds and the consequent reduction in efficiency.

Previous studies show that ionic salts are less volatile and it is this characteristic that the group headed by Professor Anta seeks to exploit. “Notwithstanding its liquid state, these types of solvents have high viscosity levels and, therefore, during the coming months we will continue our study, working on different alternatives within ionic liquids, their synthesis, etc.,” comments Elena Guillén.

The pros and cons of the new generation

Although there are already some third generation cells on the market (for example, for recharging mobile phones), according to the researchers their practical use is anecdotal. However, due to their properties of flexibility and variety of colours and shapes, the future of these cells lies in new market niches such as decoration or use in coloured windows that not only allow light through but use this light to generate electricity.

On the other hand, apart from the rapid amortisation of energy production costs -estimated in one year’s use-, there is also the low cost of the materials. “Organic materials are usually cheaper,” affirms the researcher, despite which the search continues for an alternative organic dye to the one currently used, derived from ruthenium.

“The paradox lies in the fact that if one uses these cells because their competitive edge is that they are cheaper and more readily available, and then one uses a dye based on a precious metal, what is the advantage?” points out Elena Guillén.

On the other hand, the researchers are aware that it is a relatively new technology -this type of cell was invented in 1991- that still need to be greatly developed. Furthermore, the maximum efficiency obtained in laboratory is only 11%, which is competitive but it drops when extrapolated to an industrial scale.

The main technological challenge is currently the problem of cell degradation. “If you use an organic dye, it can be degraded by the action of sunlight, with the consequent reduction in useful life compared to silicon cells. On the other hand,” the researcher highlights, “our group is working on one of the key aspect for improving cell stability – elimination of the need to use liquids that can present problems with evaporation, etc. and for which, as already mentioned, our focus is on the use of ionic salts.”

Start uga_filter:

Could sustainable architecture address pollution, climate change and resource depletion by helping us build self-sufficient, off-grid, housing from “waste”, including vehicle tires and metal drinks containers? That’s the question researchers at the University of South Australia address in a new paper appearing in the International Journal of Sustainable Design.

Martin Freney of the department of Art, Architecture and Design has taken a critical look at the work of architect, Michael Reynolds of Taos, New Mexico, USA, who has experimented with radical house designs, and construction techniques over the past three and half decades. Reynolds designs incorporate passive heating and cooling, water catchment and sewage treatment, renewable energy, and even food production. These houses, which Reynolds calls “Earthships” are essentially independent of external utilities and waste disposal. On the face of it, they offer, an environmentally benign approach to housing.

A common method of responding to unsustainable housing is to design an energy-efficient home using “natural building” methods, Freney points out. He adds that Reynolds has already demonstrated that essentially free building materials resulted in greater financial independence for the owner-occupiers of his houses and when he added off-the-grid power and water systems he found that it was possible to reduce his utilities bills to practically zero.

Freney, while enthusiastic about the potential of Reynolds’ approach is also more realistic about the actual sustainability of Earthships that are off the utility grids. After all, he says, to a certain degree, Earthships are still locked into potentially unsustainable systems because they rely on a technological society for the production of the vehicle tires and aluminum can bricks from which they are constructed and the high-tech components such as solar panels, electronics, pumps, tanks, glass and cement that allow them to go off-grid.

Freney, however, has studied the approach in more detail and suggests that the design of the Earthship could allow precious resources to be used more efficiently, effectively and durably than is possible with conventional housing. They could, he argues, “provide shelter for many decades, possibly even centuries, regardless of what happens to the infrastructure that is essential to the operation of a typical home in the developed world.”

Further research is now needed to investigate thoroughly all aspects of sustainable architecture but the early indicators suggest that the Earthship model could be entirely viable “Earthship owners start to appreciate relief from financial stresses and from knowing that they have acted to address environmental problems,” concludes Freney.

Start uga_in_feed Ending uga_in_feed: Start uga_track_user Start uga_get_option: ignore_users uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: ignore_users (1) Start uga_get_option: max_user_level uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: max_user_level (8) Tracking user with level 0 Ending uga_track_user: 1 Calling preg_replace_callback: ]*?)href\s*=\s*['"](.*?)['"]([^>]*)>(.*?) Ending uga_filter:

Could sustainable architecture address pollution, climate change and resource depletion by helping us build self-sufficient, off-grid, housing from “waste”, including vehicle tires and metal drinks containers? That’s the question researchers at the University of South Australia address in a new paper appearing in the International Journal of Sustainable Design.

Martin Freney of the department of Art, Architecture and Design has taken a critical look at the work of architect, Michael Reynolds of Taos, New Mexico, USA, who has experimented with radical house designs, and construction techniques over the past three and half decades. Reynolds designs incorporate passive heating and cooling, water catchment and sewage treatment, renewable energy, and even food production. These houses, which Reynolds calls “Earthships” are essentially independent of external utilities and waste disposal. On the face of it, they offer, an environmentally benign approach to housing.

A common method of responding to unsustainable housing is to design an energy-efficient home using “natural building” methods, Freney points out. He adds that Reynolds has already demonstrated that essentially free building materials resulted in greater financial independence for the owner-occupiers of his houses and when he added off-the-grid power and water systems he found that it was possible to reduce his utilities bills to practically zero.

Freney, while enthusiastic about the potential of Reynolds’ approach is also more realistic about the actual sustainability of Earthships that are off the utility grids. After all, he says, to a certain degree, Earthships are still locked into potentially unsustainable systems because they rely on a technological society for the production of the vehicle tires and aluminum can bricks from which they are constructed and the high-tech components such as solar panels, electronics, pumps, tanks, glass and cement that allow them to go off-grid.

Freney, however, has studied the approach in more detail and suggests that the design of the Earthship could allow precious resources to be used more efficiently, effectively and durably than is possible with conventional housing. They could, he argues, “provide shelter for many decades, possibly even centuries, regardless of what happens to the infrastructure that is essential to the operation of a typical home in the developed world.”

Further research is now needed to investigate thoroughly all aspects of sustainable architecture but the early indicators suggest that the Earthship model could be entirely viable “Earthship owners start to appreciate relief from financial stresses and from knowing that they have acted to address environmental problems,” concludes Freney.

Start uga_filter:

As manufacturers of consumer digital cameras compete in increments, adding one or two megapixels to their latest models, David Brady of Duke University is thinking much bigger. Working with the U.S. Department of Defense’s Defense Advanced Research Projects Agency, he is designing and building a camera that could achieve resolutions 1,000 or even 1 million times greater than the technology on the market today

The goal of reaching giga- or terapixels, says Brady, is currently being held back by the difficulty of designing a spherical lens that will not distort small areas of a scene. His idea is not only to modify the shape of the camera lens — making it aspherical — but to link together thousands of microcameras behind the main lens. Each of these cameras would have its own lens optimized for a small portion of the field of view.

“Now, when you use a camera, you’re looking through a narrow soda straw,” says Brady. “These new cameras will be able to capture the full view of human vision.”

The final result of the three-year project should be a device about the size of a breadbox, though Brady hopes to scale the technology down to create a single-lens reflex camera with a resolution of 50 gigapixels.

Reference: Paper CWB2, “Multiscale Optical Systems” is at 2 p.m. Wednesday, Oct. 14.

The latest technology in optics and lasers will be on display at the Optical Society’s (OSA) Annual Meeting, Frontiers in Optics (FiO), which takes place Oct. 11-15 at the Fairmont San Jose Hotel and the Sainte Claire Hotel in San Jose, Calif.


Start uga_in_feed Ending uga_in_feed: Start uga_track_user Start uga_get_option: ignore_users uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: ignore_users (1) Start uga_get_option: max_user_level uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: max_user_level (8) Tracking user with level 0 Ending uga_track_user: 1 Calling preg_replace_callback: ]*?)href\s*=\s*['"](.*?)['"]([^>]*)>(.*?) Ending uga_filter:

As manufacturers of consumer digital cameras compete in increments, adding one or two megapixels to their latest models, David Brady of Duke University is thinking much bigger. Working with the U.S. Department of Defense’s Defense Advanced Research Projects Agency, he is designing and building a camera that could achieve resolutions 1,000 or even 1 million times greater than the technology on the market today

The goal of reaching giga- or terapixels, says Brady, is currently being held back by the difficulty of designing a spherical lens that will not distort small areas of a scene. His idea is not only to modify the shape of the camera lens — making it aspherical — but to link together thousands of microcameras behind the main lens. Each of these cameras would have its own lens optimized for a small portion of the field of view.

“Now, when you use a camera, you’re looking through a narrow soda straw,” says Brady. “These new cameras will be able to capture the full view of human vision.”

The final result of the three-year project should be a device about the size of a breadbox, though Brady hopes to scale the technology down to create a single-lens reflex camera with a resolution of 50 gigapixels.

Reference: Paper CWB2, “Multiscale Optical Systems” is at 2 p.m. Wednesday, Oct. 14.

The latest technology in optics and lasers will be on display at the Optical Society’s (OSA) Annual Meeting, Frontiers in Optics (FiO), which takes place Oct. 11-15 at the Fairmont San Jose Hotel and the Sainte Claire Hotel in San Jose, Calif.


Start uga_filter:

NASA’s Interstellar Boundary Explorer, or IBEX, spacecraft has made it possible for scientists to construct the first comprehensive sky map of our solar system and its location in the Milky Way galaxy. The new view will change the way researchers view and study the interaction between our galaxy and sun.

The Interstellar Boundary Explorer (IBEX) mission science team has used data from NASAs IBEX spacecraft to construct the first-ever all-sky map of the interactions occurring at the edge of the solar system, where the suns influence diminishes and interacts with the interstellar medium. Among the findings is an unexpectedly bright ribbon-like emission. (Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio)

The Interstellar Boundary Explorer (IBEX) mission science team has used data from NASA's IBEX spacecraft to construct the first-ever all-sky map of the interactions occurring at the edge of the solar system, where the sun's influence diminishes and interacts with the interstellar medium. Among the findings is an unexpectedly bright ribbon-like emission. (Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio)

The sky map was produced with data that two detectors on the spacecraft collected during six months of observations. The detectors measured and counted particles scientists refer to as energetic neutral atoms.

The energetic neutral atoms are created in an area of our solar system known as the interstellar boundary region. This region is where charged particles from the sun, called the solar wind, flow outward far beyond the orbits of the planets and collide with material between stars. The energetic neutral atoms travel inward toward the sun from interstellar space at velocities ranging from 100,000 mph to more than 2.4 million mph. This interstellar boundary emits no light that can be collected by conventional telescopes.

The new map reveals the region that separates the nearest reaches of our galaxy, called the local interstellar medium, from our heliosphere — a protective bubble that shields and protects our solar system from most of the dangerous cosmic radiation traveling through space.

“For the first time, we’re sticking our heads out of the sun’s atmosphere and beginning to really understand our place in the galaxy,” said David J. McComas, IBEX principal investigator and assistant vice president of the Space Science and Engineering Division at Southwest Research Institute in San Antonio. “The IBEX results are truly remarkable, with a narrow ribbon of bright details or emissions not resembling any of the current theoretical models of this region.”

NASA released the sky map image Oct. 15 in conjunction with publication of the findings in the journal Science. The IBEX data were complemented and extended by information collected using an imaging instrument sensor on NASA’s Cassini spacecraft. Cassini has been observing Saturn, its moons and rings since the spacecraft entered the planet’s orbit in 2004.

The IBEX sky maps also put observations from NASA’s Voyager spacecraft into context. The twin Voyager spacecraft, launched in 1977, traveled to the outer solar system to explore Jupiter, Saturn, Uranus and Neptune. In 2007, Voyager 2 followed Voyager 1 into the interstellar boundary. Both spacecraft are now in the midst of this region where the energetic neutral atoms originate. However, the IBEX results show a ribbon of bright emissions undetected by the two Voyagers.

“The Voyagers are providing ground truth, but they’re missing the most exciting region,” said Eric Christian, the IBEX deputy mission scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md. “It’s like having two weather stations that miss the big storm that runs between them.”

The IBEX spacecraft was launched in October 2008. Its science objective was to discover the nature of the interactions between the solar wind and the interstellar medium at the edge of our solar system. The Southwest Research Institute developed and leads the mission with a team of national and international partners. The spacecraft is the latest in NASA’s series of low-cost, rapidly developed Small Explorers Program. NASA’s Goddard Space Flight Center manages the program for the agency’s Science Mission Directorate at NASA Headquarters in Washington.

The Cassini-Huygens mission is a cooperative project of NASA and the European and Italian Space Agencies. NASA’s Jet Propulsion Laboratory in Pasadena, Calif., provides overall management for Cassini and the Voyagers for the Science Mission Directorate.

To view the sky map and for more information about IBEX, visit: http://www.nasa.gov/ibex

Start uga_in_feed Ending uga_in_feed: Start uga_track_user Start uga_get_option: ignore_users uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: ignore_users (1) Start uga_get_option: max_user_level uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: max_user_level (8) Tracking user with level 0 Ending uga_track_user: 1 Calling preg_replace_callback: ]*?)href\s*=\s*['"](.*?)['"]([^>]*)>(.*?) Start uga_preg_callback: Array Get tracker for full url Start uga_track_full_url: www.nasa.gov/ibex Start uga_is_url_internal: www.nasa.gov/ibex Start uga_get_option: internal_domains uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: internal_domains (www.humacon.org,humacon.org) Checking hostname www.humacon.org Checking hostname humacon.org Ending uga_is_url_internal: Get tracker for external URL Start uga_track_external_url: www.nasa.gov/ibex Start uga_get_option: track_ext_links uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: track_ext_links (1) Tracking external links enabled Start uga_get_option: prefix_ext_links uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: prefix_ext_links (/outgoing/) Ending uga_track_external_url: www.nasa.gov/ibex Ending uga_track_full_url: /outgoing/www.nasa.gov/ibex Adding onclick attribute for /outgoing/www.nasa.gov/ibex Ending uga_preg_callback: http://www.nasa.gov/ibex Ending uga_filter:

NASA’s Interstellar Boundary Explorer, or IBEX, spacecraft has made it possible for scientists to construct the first comprehensive sky map of our solar system and its location in the Milky Way galaxy. The new view will change the way researchers view and study the interaction between our galaxy and sun.

The Interstellar Boundary Explorer (IBEX) mission science team has used data from NASAs IBEX spacecraft to construct the first-ever all-sky map of the interactions occurring at the edge of the solar system, where the suns influence diminishes and interacts with the interstellar medium. Among the findings is an unexpectedly bright ribbon-like emission. (Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio)

The Interstellar Boundary Explorer (IBEX) mission science team has used data from NASA's IBEX spacecraft to construct the first-ever all-sky map of the interactions occurring at the edge of the solar system, where the sun's influence diminishes and interacts with the interstellar medium. Among the findings is an unexpectedly bright ribbon-like emission. (Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio)

The sky map was produced with data that two detectors on the spacecraft collected during six months of observations. The detectors measured and counted particles scientists refer to as energetic neutral atoms.

The energetic neutral atoms are created in an area of our solar system known as the interstellar boundary region. This region is where charged particles from the sun, called the solar wind, flow outward far beyond the orbits of the planets and collide with material between stars. The energetic neutral atoms travel inward toward the sun from interstellar space at velocities ranging from 100,000 mph to more than 2.4 million mph. This interstellar boundary emits no light that can be collected by conventional telescopes.

The new map reveals the region that separates the nearest reaches of our galaxy, called the local interstellar medium, from our heliosphere — a protective bubble that shields and protects our solar system from most of the dangerous cosmic radiation traveling through space.

“For the first time, we’re sticking our heads out of the sun’s atmosphere and beginning to really understand our place in the galaxy,” said David J. McComas, IBEX principal investigator and assistant vice president of the Space Science and Engineering Division at Southwest Research Institute in San Antonio. “The IBEX results are truly remarkable, with a narrow ribbon of bright details or emissions not resembling any of the current theoretical models of this region.”

NASA released the sky map image Oct. 15 in conjunction with publication of the findings in the journal Science. The IBEX data were complemented and extended by information collected using an imaging instrument sensor on NASA’s Cassini spacecraft. Cassini has been observing Saturn, its moons and rings since the spacecraft entered the planet’s orbit in 2004.

The IBEX sky maps also put observations from NASA’s Voyager spacecraft into context. The twin Voyager spacecraft, launched in 1977, traveled to the outer solar system to explore Jupiter, Saturn, Uranus and Neptune. In 2007, Voyager 2 followed Voyager 1 into the interstellar boundary. Both spacecraft are now in the midst of this region where the energetic neutral atoms originate. However, the IBEX results show a ribbon of bright emissions undetected by the two Voyagers.

“The Voyagers are providing ground truth, but they’re missing the most exciting region,” said Eric Christian, the IBEX deputy mission scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md. “It’s like having two weather stations that miss the big storm that runs between them.”

The IBEX spacecraft was launched in October 2008. Its science objective was to discover the nature of the interactions between the solar wind and the interstellar medium at the edge of our solar system. The Southwest Research Institute developed and leads the mission with a team of national and international partners. The spacecraft is the latest in NASA’s series of low-cost, rapidly developed Small Explorers Program. NASA’s Goddard Space Flight Center manages the program for the agency’s Science Mission Directorate at NASA Headquarters in Washington.

The Cassini-Huygens mission is a cooperative project of NASA and the European and Italian Space Agencies. NASA’s Jet Propulsion Laboratory in Pasadena, Calif., provides overall management for Cassini and the Voyagers for the Science Mission Directorate.

To view the sky map and for more information about IBEX, visit: http://www.nasa.gov/ibex

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New York City plans to train one thousand superintendents on green buildings this year. City managers of commercial and high-rise residential buildings now have the chance reduce greenhouse gas emissions in the city on a sky high level.


Mayor Michael Bloomberg took part in the program, “One Year, One Thousand Green Supers” which was also approved by the U.S. Green Building Council and the Building Performance Institute. It’s also made possible by the Thomas Shortman Training Fund. This is part of NYC’s huge goal to reduce their building-generated carbon footprint.

The program will include:

  • a 40-hour (minimum) class and hand on training.
  • instruction for building service workers with top-notch practices in energy-efficient operations.
  • projects to identify and address wasted energy.
  • the creation of a a green operating plan for each super participating.
  • ways to perform cost-benefit analysis for building owners and managers interested in going green.
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Start uga_preg_callback: Array Get tracker for full url Start uga_track_full_url: search.yahoo.com/search;_ylt=A0oGki.kldZKB4IAJ5dXNyoA?p=One+Year%2C+One+Thousand+Green+Supers&fr2=sb-top&fr=moz35&sao=1 Start uga_is_url_internal: search.yahoo.com/search;_ylt=A0oGki.kldZKB4IAJ5dXNyoA?p=One+Year%2C+One+Thousand+Green+Supers&fr2=sb-top&fr=moz35&sao=1 Start uga_get_option: internal_domains uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: internal_domains (www.humacon.org,humacon.org) Checking hostname www.humacon.org Checking hostname humacon.org Ending uga_is_url_internal: Get tracker for external URL Start uga_track_external_url: search.yahoo.com/search;_ylt=A0oGki.kldZKB4IAJ5dXNyoA?p=One+Year%2C+One+Thousand+Green+Supers&fr2=sb-top&fr=moz35&sao=1 Start uga_get_option: track_ext_links uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: track_ext_links (1) Tracking external links enabled Start uga_get_option: prefix_ext_links uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' => true, 'max_user_level' => '8', 'footer_hooked' => true, 'filter_content' => true, 'filter_comments' => true, 'filter_comment_authors' => true, 'track_ext_links' => true, 'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: prefix_ext_links (/outgoing/) Ending uga_track_external_url: search.yahoo.com/search;_ylt=A0oGki.kldZKB4IAJ5dXNyoA?p=One+Year%2C+One+Thousand+Green+Supers&fr2=sb-top&fr=moz35&sao=1 Ending uga_track_full_url: /outgoing/search.yahoo.com/search;_ylt=A0oGki.kldZKB4IAJ5dXNyoA?p=One+Year%2C+One+Thousand+Green+Supers&fr2=sb-top&fr=moz35&sao=1 Adding onclick attribute for /outgoing/search.yahoo.com/search;_ylt=A0oGki.kldZKB4IAJ5dXNyoA?p=One+Year%2C+One+Thousand+Green+Supers&fr2=sb-top&fr=moz35&sao=1 Ending uga_preg_callback: One Year, One Thousand Green Supers Start uga_preg_callback: Array Get tracker for full url Start uga_track_full_url: www.usgbc.org/ Start uga_is_url_internal: www.usgbc.org/ Start uga_get_option: internal_domains uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 'ignore_users' 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'prefix_ext_links' => '/outgoing/', 'track_files' => true, 'prefix_file_links' => '/downloads/', 'track_extensions' => 'gif,jpg,jpeg,bmp,png,pdf,mp3,wav,phps,zip,gz,tar,rar,jar,exe,pps,ppt,xls,doc', 'track_mail_links' => true, 'prefix_mail_links' => '/mailto/', 'debug' => true, 'check_updates' => true, 'version_sent' => '1.6.0', 'advanced_config' => true, ) Ending uga_get_option: prefix_ext_links (/outgoing/) Ending uga_track_external_url: www.usgbc.org/ Ending uga_track_full_url: /outgoing/www.usgbc.org/ Adding onclick attribute for /outgoing/www.usgbc.org/ Ending uga_preg_callback: U.S. Green Building Council Start uga_preg_callback: Array Get tracker for full url Start uga_track_full_url: www.bpi.org/content/home/index.php Start uga_is_url_internal: www.bpi.org/content/home/index.php Start uga_get_option: internal_domains uga_options: array ( 'internal_domains' => 'www.humacon.org,humacon.org', 'account_id' => 'UA-10399907-2', 'enable_tracker' => true, 'track_adm_pages' => false, 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New York City plans to train one thousand superintendents on green buildings this year. City managers of commercial and high-rise residential buildings now have the chance reduce greenhouse gas emissions in the city on a sky high level.


Mayor Michael Bloomberg took part in the program, “One Year, One Thousand Green Supers” which was also approved by the U.S. Green Building Council and the Building Performance Institute. It’s also made possible by the Thomas Shortman Training Fund. This is part of NYC’s huge goal to reduce their building-generated carbon footprint.

The program will include:

  • a 40-hour (minimum) class and hand on training.
  • instruction for building service workers with top-notch practices in energy-efficient operations.
  • projects to identify and address wasted energy.
  • the creation of a a green operating plan for each super participating.
  • ways to perform cost-benefit analysis for building owners and managers interested in going green.
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In the past 5 years, no material has excited more interest from condensed matter physicists than graphene, a sheet of carbon only one atom thick. Electrons zing through the stuff in an unusual way, and they flow so easily that graphene could someday replace silicon and other semiconductors as the material of choice for microchips. Now, a team of physicists has taken a key step in fulfilling graphene’s promise as a hotbed of exotic physics by showing that the electrons within it can team up to behave like particles with a fraction of the electron’s charge.

The effect is called the fractional quantum Hall effect, and it’s an esoteric embellishment of an already esoteric phenomenon known as the Hall effect. Discovered in 1879, the Hall effect works like this: Suppose you take a horizontal bar of metal and apply a voltage from one end to the other. A current will run down the length of the bar. If you then apply a strong vertical magnetic field, the flowing electrons will experience a sideways shove that will cause them to crowd to the side of the bar as they go so that a voltage develops across the width of the bar too. Sideways Hall voltage increases in proportion to the strength of the magnetic field.

Things get weirder if the bar is made of semiconductor and is extremely thin top to bottom. In that case, the electrons can flow in only a few quantum channels that close one by one as the magnetic field increases. The Hall voltage climbs as the magnetic field increases in a series of even steps whose spacing is set by the electron’s charge. The discovery of that quantum Hall effect won the Nobel Prize in physics in 1985. Weirder still, if the slab of semiconductor is made very pure and cold, then the electrons can gang up to act like “quasiparticles” with fractional charges–say, 1/3 of an electron’s charge–adding more steps to the Hall-voltage stairway. That’s the fractional quantum Hall effect, which bagged a Nobel in 1988.

The fractional effect is a sign of very strong interactions among the electrons, a condition that can lead to a variety of surprising phenomena and which marks the conceptual frontier in condensed matter physics. Many physicists had hoped to see the fractional effect in graphene as proof that it would be an especially fruitful material to study. But they couldn’t be entirely sure it would appear. Because of the arrangement of the atoms in graphene, the electrons zip through less like ordinary massive particles that can stop and start and more like massless and always-moving particles of light. Nobody was sure such “relativistic” electrons would interact strongly enough to produce the effect, though several groups had looked for it. “It was the biggest disappointment in this really hot field, that it hadn’t been seen,” says Eva Andrei of Rutgers University in Piscataway, New Jersey.

Fret no more, physicists. Andrei and her team have finally spotted electrons in graphene getting together in the right way. To do it, the team suspended micrometer-sized bits of graphene to avoid interference from the underlying substrate. The researchers then used a special arrangement of electrodes to keep from shorting out their own measurements, they report online this week in Nature. They observed quasiparticles with 1/3 an electron’s charge. In fact, Andrei says, the researchers saw the effect at higher temperatures and lower magnetic fields than are needed to see it in semiconductors, suggesting that the electrons in graphene interact especially strongly.

“It’s absolutely convincing,” says physicist Kostya Novoselov of the University of Manchester, U.K. “It definitely proves it’s reasonable to study electron-electron interactions in graphene.” Andrei says now that physicists have spotted this effect, they may see electrons in graphene joining together in completely new and even weirder ways. And if researchers can produce quasiparticles with charge 5/2, then in principle they could make a type of quantum computer that would work by braiding the particles’ paths together.

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In the past 5 years, no material has excited more interest from condensed matter physicists than graphene, a sheet of carbon only one atom thick. Electrons zing through the stuff in an unusual way, and they flow so easily that graphene could someday replace silicon and other semiconductors as the material of choice for microchips. Now, a team of physicists has taken a key step in fulfilling graphene’s promise as a hotbed of exotic physics by showing that the electrons within it can team up to behave like particles with a fraction of the electron’s charge.

The effect is called the fractional quantum Hall effect, and it’s an esoteric embellishment of an already esoteric phenomenon known as the Hall effect. Discovered in 1879, the Hall effect works like this: Suppose you take a horizontal bar of metal and apply a voltage from one end to the other. A current will run down the length of the bar. If you then apply a strong vertical magnetic field, the flowing electrons will experience a sideways shove that will cause them to crowd to the side of the bar as they go so that a voltage develops across the width of the bar too. Sideways Hall voltage increases in proportion to the strength of the magnetic field.

Things get weirder if the bar is made of semiconductor and is extremely thin top to bottom. In that case, the electrons can flow in only a few quantum channels that close one by one as the magnetic field increases. The Hall voltage climbs as the magnetic field increases in a series of even steps whose spacing is set by the electron’s charge. The discovery of that quantum Hall effect won the Nobel Prize in physics in 1985. Weirder still, if the slab of semiconductor is made very pure and cold, then the electrons can gang up to act like “quasiparticles” with fractional charges–say, 1/3 of an electron’s charge–adding more steps to the Hall-voltage stairway. That’s the fractional quantum Hall effect, which bagged a Nobel in 1988.

The fractional effect is a sign of very strong interactions among the electrons, a condition that can lead to a variety of surprising phenomena and which marks the conceptual frontier in condensed matter physics. Many physicists had hoped to see the fractional effect in graphene as proof that it would be an especially fruitful material to study. But they couldn’t be entirely sure it would appear. Because of the arrangement of the atoms in graphene, the electrons zip through less like ordinary massive particles that can stop and start and more like massless and always-moving particles of light. Nobody was sure such “relativistic” electrons would interact strongly enough to produce the effect, though several groups had looked for it. “It was the biggest disappointment in this really hot field, that it hadn’t been seen,” says Eva Andrei of Rutgers University in Piscataway, New Jersey.

Fret no more, physicists. Andrei and her team have finally spotted electrons in graphene getting together in the right way. To do it, the team suspended micrometer-sized bits of graphene to avoid interference from the underlying substrate. The researchers then used a special arrangement of electrodes to keep from shorting out their own measurements, they report online this week in Nature. They observed quasiparticles with 1/3 an electron’s charge. In fact, Andrei says, the researchers saw the effect at higher temperatures and lower magnetic fields than are needed to see it in semiconductors, suggesting that the electrons in graphene interact especially strongly.

“It’s absolutely convincing,” says physicist Kostya Novoselov of the University of Manchester, U.K. “It definitely proves it’s reasonable to study electron-electron interactions in graphene.” Andrei says now that physicists have spotted this effect, they may see electrons in graphene joining together in completely new and even weirder ways. And if researchers can produce quasiparticles with charge 5/2, then in principle they could make a type of quantum computer that would work by braiding the particles’ paths together.

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