Entries with tag lawrence berkeley national laboratory.

Scientists Create Sensitive Electronic Whiskers

Researchers from the US Lawrence Berkeley National Laboratory and the University of California, Berkeley, scientists have developed extremely sensitive sensors inspired by animal whiskers. These tactile sensors, sensitive to even very light pressure, consist of composite carbon-nanotube films and silver nanoparticles applied to fibers. The researchers explain the sensitivity is a product of using elastic fibers that respond to even the slightest amount of pressure. The scientists say the whiskers’ sensitivity and electrical can be tuned by changing the ratio of the components used. Mammals and insects use their hairlike whiskers as sensors for monitoring wind and for navigation. The researchers’ sensors were able to accurately complete 2D and 3D wind-flow mapping. They say their whiskers could also be used for spatial mapping as well as in sensors that measure wearers’ heartbeat and pulse rate. The scientists published their work in the Proceedings of the National Academy of Sciences. (National Monitor)(University of California Berkeley Research)(Proceedings of the National Academy of Sciences)

Server Farms Can be More Sustainable

New research claims server farms can be made more sustainable through a combination of using clean energy, modern equipment and locating data farms in cooler climates. The report -- by Stanford University, Northwestern University and the Lawrence Berkeley National Laboratory researchers – claims these moves could make these facilities
88 percent more sustainable. Using current IT equipment alone, could reduce server farm greenhouse gas emissions by 80 percent, according to the researchers. Another 8 percent reduction could be possible if these facilities were in cooler locations, requiring less energy. Another significant problem, according to the study, are so-called zombie servers, hardware that stays on and uses energy, but is not being used for computational tasks. The findings were published earlier this summer in the journal Nature Climate Change. (The Guardian)(Nature Climate Change)

Expert: Exaflops Supercomputing Is Unlikely in the Near Future

The much-discussed idea that supercomputing performance could soon reach exaflops (1018 floating point operations per second) levels will not be possible before the end of the decade, according to Horst Simon, the US Lawrence Berkeley National Laboratory’s deputy director. A combination of technical challenges are proving an obstacle, including the total power needed by such a system, increased chip power efficiency, and the cost of data movement and memory. “I also think calling the system exa-anything is a bad idea. It’s become a bad brand, associated with buying big machines for a few national labs,” he told HPCWire. “It also sets the community up for a perceived failure if we don’t get to exaflops.” And measuring the system’s performance once it is built also poses a challenge, he adds, estimating an exascale system will need five to six days to run the LINPACK benchmark. A reasonable goal toward exascale computing, Simon said, would be constructing an exascale system that could rank first in the TOP500 supercomputing-performance list by 2020. He says there are projects working in that direction, including the US Department of Energy’s FastForward. Simon says the US needs exascale computing resources to maintain a competitive advantage in manufacturing as well as for national security. (SlashDot)(HPCWire)(Scientific Computing)(“No Exaflops for You,” Horst Simon)

Researchers Make Solar Cells from Semiconductor Materials

Researchers from the US Department of Energy’s Lawrence Berkeley National Laboratory and the University of California, Berkeley have devised a way to make low-cost, highly efficient solar cells from virtually any semiconductor material. This would let manufacturers use inexpensive materials previously deemed unsuitable for solar cell manufacturing, such as metal oxides, sulfides, and phosphides. The researchers say their technique could stimulate solar energy use. “It’s time we put bad materials to good use,” stated Alex Zettl,  physics professor at UC Berkeley and director of the Center of Integrated Nanomechanical Systems -- who is leading the research. “Our technology allows us to sidestep the difficulty in chemically tailoring many earth abundant, nontoxic semiconductors and instead tailor these materials simply by applying an electric field.” Typically, solar cells are made from expensive photovoltaic materials such as cadmium telluride or copper indium gallium selenide thin films. The researchers’ screening-engineered field-effect photovoltaics method uses an electric field effect, rather than chemical dopants, to alter a semiconductor’s conductive capabilities. The technique also creates devices that perform self-gating functions, which means they do not need external power for gating. These gates can also function as an antireflection coating. The researchers published their work in Nano Letters. (Science Daily)(Lawrence Berkeley National Laboratory)(Nano Letters)

Researchers Develop Nanoscale Optical Equipment

A team headed by scientists from the US Department of Energy’s Lawrence Berkeley National Laboratory and the University of California, Berkeley have developed what they say are world’s smallest 3D optical cavities, components in an optical system that allow a beam to travel through a closed path,  with the potential to generate intense nanolaser beams. The optical cavities could be used in various optical devices, including nanolasers, LEDs, photonic integrated circuits, optical sensors, and photonic communications. The researchers built the optical cavities with an indefinite metamaterial created with ultrathin silver and germanium layers. These materials can bend light backward in some directions, a property known as negative refraction. The material also enabled researchers to make very small optical cavities able to be used in smaller devices and to take advantage of electromagnetic behavior not found in naturally occurring materials. This allows the cavities, for example, to be different sizes, but still have the same resonance frequency. The scientists published their work in Nature Photonics. (Science Daily)(Lawrence Berkeley National Laboratory)(Nature Photonics)

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