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    New Thermoelectric Material with High Power Factors

    November 17, 2016, Categories  Physics, Technology/Electronics

    Ohio State University researchers have developed a technique to create light emitting diodes on metal foil. Image by Brelon J. May, courtesy of The Ohio State University.

    Ohio State University researchers have developed a technique to create light emitting diodes on metal foil. Image by Brelon J. May, courtesy of The Ohio State University.

    Material created with high heat yields record power output density. With energy conservation expected to play a growing role in managing global demand, materials and methods that make better use of existing sources of energy have become increasingly important. Researchers reported this week they have demonstrated a step forward in converting waste heat – from industrial smokestacks, power generating plants or even automobile tailpipes – into electricity.

    The work, using a thermoelectric compound composed of niobium, titanium, iron and antimony, succeeded in raising the material’s power output density dramatically by using...

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    Laser Spectroscopy of Ultrathin Semiconductor reveals rise of ‘Trion’ Quasiparticles: central to Energy Apps

    October 8, 2015, Categories  Physics, Technology/Electronics

    In a pump-probe experiment, the pump laser pulse first excites the 2D material, and later, at controllable time-delays, the probe laser pulse returns to the energy-pumped site to provide information about the evolution of the pump’s effect on the material. In the ORNL experiment, absorption of pumped energy first generated two excitons, X1 and X2. Dissociation of these excitons through hole trapping at the substrate freed their electrons. Then the arriving probe pulse generated new electron–hole pairs, which joined the remaining free electrons to form trions T1 and T2. Credit: Oak Ridge National Laboratory, U.S. Dept. of Energy

    In a pump-probe experiment, the pump laser pulse first excites the 2D material, and later, at controllable time-delays, the probe laser pulse returns to the energy-pumped site to provide information about the evolution of the pump’s effect on the material. In the ORNL experiment, absorption of pumped energy first generated two excitons, X1 and X2. Dissociation of these excitons through hole trapping at the substrate freed their electrons. Then the arriving probe pulse generated new electron–hole pairs, which joined the remaining free electrons to form trions T1 and T2. Credit: Oak Ridge National Laboratory, U.S. Dept. of Energy

    Quasiparticles – excitations that behave collectively like particles – can be difficult to detect...

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