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arXiv · 1105.1350

Optical excitation of Electron-Glasses

Z. Ovadyahu
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Abstract

Electron-glasses can be readily driven far from equilibrium by a variety of means. Several mechanisms to excite the system and their relative merits are reviewed. In this study we focus on the process of exciting electron-glasses by interaction with near infrared radiation. The efficiency of this protocol varies considerably among different electron-glasses, but it only weakly depends on their resistance at liquid helium temperatures. A dramatic enhancement of the excitation efficiency is observed upon doping crystalline indium-oxide with Au. Some enhancement is observed also in samples doped with Pb but this enhancement fades away with time unlike the situation in the Au-doped samples. Several structural and analytical tools are used to characterize the changes in the materials that may be responsible for these effects. Possible routes by which high-frequency electromagnetic fields take the system far from equilibrium are discussed.

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Z. Ovadyahu. 2011-05-06. Optical excitation of Electron-Glasses. https://doi.org/10.1103/physrevb.83.235126

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