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arXiv · 0706.2913

Observation of strong electron dephasing in disordered Cu$_{93}$Ge$_4$Au$_3$ thin films

S. M. Huang·T. C. Lee·H. Akimoto·K. Kono·J. J. Lin
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Abstract

We report the observation of strong electron dephasing in a series of disordered Cu$_{93}$Ge$_4$Au$_3$ thin films. A very short electron dephasing time possessing very weak temperature dependence around 6 K, followed by an upturn with further decrease in temperature below 4 K, is found. The upturn is progressively more pronounced in more disordered samples. Moreover, a ln$T$ dependent, but high-magnetic-field-insensitive, resistance rise persisting from above 10 K down to 30 mK is observed in the films. These results suggest a nonmagnetic dephasing process which is stronger than any known mechanism and may originate from the coupling of conduction electrons to dynamic defects.

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S. M. Huang, T. C. Lee, H. Akimoto, K. Kono, J. J. Lin. 2007-06-20. Observation of strong electron dephasing in disordered Cu$_{93}$Ge$_4$Au$_3$ thin films. https://doi.org/10.1103/physrevlett.99.046601

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