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Metal-insulator transition and glassy behavior in two-dimensional electron systems

D. Popovic·S. Bogdanovich·J. Jaroszynski·T. M. Klapwijk
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Abstract

Studies of low-frequency resistance noise demonstrate that glassy freezing occurs in a two-dimensional electron system in silicon in the vicinity of the metal-insulator transition (MIT). The width of the metallic glass phase, which separates the 2D metal and the (glassy) insulator, depends strongly on disorder, becoming extremely small in high-mobility (low-disorder) samples. The glass transition is manifested by a sudden and dramatic slowing down of the electron dynamics, and by a very abrupt change to the sort of statistics characteristic of complicated multistate systems. In particular, the behavior of the second spectrum, an important fourth-order noise statistic, indicates the presence of long-range correlations between fluctuators in the glassy phase, consistent with the hierarchical picture of glassy dynamics.

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D. Popovic, S. Bogdanovich, J. Jaroszynski, T. M. Klapwijk. 2004-02-20. Metal-insulator transition and glassy behavior in two-dimensional electron systems. https://doi.org/10.1117/12.488847

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