Category Physics

Common Glass used to Optimize Graphene’s Electronic Properties

Left: This is a schematic of a graphene field-effect-transistor used in this study. The device consists of a solar cell containing graphene stacked on top of a high-performance copper indium gallium diselenide (CIGS) semiconductor, which in turn is stacked on an industrial substrate (either soda-lime glass, SLG, or sodium-free borosilicate glass, BSG). The research revealed that the SLG substrate serves as a source of sodium doping, and improved device performance in a way not seen in the sodium-free substrate. Right: A scanning electron micrograph of the device as seen from above, with the white scale bar measuring 10 microns, and a transmission electron micrograph inset of the CIGS/graphene interface where the white scale bar measures 100 nanometers. Credit: Brookhaven National Laboratory

Left: This is a schematic of a graphene field-effect-transistor used in this study. The device consists of a solar cell containing graphene stacked on top of a high-performance copper indium gallium diselenide (CIGS) semiconductor, which in turn is stacked on an industrial substrate (either soda-lime glass, SLG, or sodium-free borosilicate glass, BSG). The research revealed that the SLG substrate serves as a source of sodium doping, and improved device performance in a way not seen in the sodium-free substrate. Right: A scanning electron micrograph of the device as seen from above, with the white scale bar measuring 10 microns, and a transmission electron micrograph inset of the CIGS/graphene interface where the white scale bar measures 100 nanometers...

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Most Precise Measurement of Reactor Antineutrino Spectrum Reveals intriguing Surprise

Most precise measurement of reactor Antineutrino spectrum reveals intriguing surprise

The Daya Bay experiment measures the antineutrinos produced by the reactors of the Daya Bay Nuclear Power Plant and the Ling Ao Nuclear Power Plant in mainland China. The photo shows a panoramic view of the Daya Bay reactor complex. Credit: Roy Kaltschmidt, Berkeley Lab

Members of the International Daya Bay Collaboration, who track the production and flavor-shifting behavior of electron antineutrinos generated at a nuclear power complex in China, have obtained the most precise measurement of these subatomic particles’ energy spectrum ever recorded. The data generated from the world’s largest sample of reactor antineutrinos indicate 2 intriguing discrepancies with theoretical predictions and provide an important measurement that will shape future reactor neutrino experiments.

Studying the b...

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Silicon Chip with Integrated Laser: Light from a Nanowire: Nanolaser for information technology

Gallium-arsenide nanowires are on a silicon surface. Credit: Thomas Stettner/Philipp Zimmermann / TUM

Gallium-arsenide nanowires are on a silicon surface. Credit: Thomas Stettner/Philipp Zimmermann / TUM

Physicists at the Technical University of Munich (TUM) have developed a nanolaser, a thousand times thinner than a human hair. Thanks to an ingenious process, the nanowire lasers grow right on a silicon chip, making it possible to produce high-performance photonic components cost-effectively. This will pave the way for fast and efficient data processing with light in the future. Ever smaller, ever faster, ever cheaper – since the start of the computer age the performance of processors has doubled on average every 18 months. 50 years ago already, Intel co-founder Gordon E. Moore prognosticated this astonishing growth in performance. And Moore’s law seems to hold true to this day.

But the mi...

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A Metal that behaves like Water: New behaviors of graphene

In a new paper published in Science, researchers at the Harvard and Raytheon BBN Technology have advanced our understanding of graphene's basic properties, observing for the first time electrons in a metal behaving like a fluid. Credit: Peter Allen/Harvard SEAS

In a new paper published in Science, researchers at the Harvard and Raytheon BBN Technology have advanced our understanding of graphene’s basic properties, observing for the first time electrons in a metal behaving like a fluid. Credit: Peter Allen/Harvard SEAS

Researchers have made a breakthrough in our understanding of graphene’s basic properties, observing for the first time electrons in a metal behaving like a fluid. This research could lead to novel thermoelectric devices as well as provide a model system to explore exotic phenomena like black holes and high-energy plasmas. In order to make this observation, the team improved methods to create ultra-clean graphene and developed a new way measure its thermal conductivity.

In ordinary, 3D metals, electrons hardly interact with each othe...

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