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arXiv · 0710.2637

Relaxation dynamics in quantum electron-glasses

Z. Ovadyahu
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Abstract

It is experimentally shown that, depending on the carrier-concentration of the system $n$, the dynamics of electron-glasses either \textit{slows down }with increasing temperature or it is \textit{independent} of it. This also correlates with the dependence of a typical relaxation time (or `viscosity') on $n$. These linked features are argued to be consistent with a model for dissipative tunneling. The slow relaxation of the electron glass may emerge then as a manifestation of friction in a many-body quantum system. Our considerations may also explain why strongly-localized granular metals are likely to show electron-glass effects while semiconductors are not.

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Z. Ovadyahu. 2007-11-28. Relaxation dynamics in quantum electron-glasses. https://doi.org/10.1103/physrevlett.99.226603

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