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Time-dependent Effects in the Metallic Phase in Si-MOS: Evidence for Non-Diffusive Transport

V. M. Pudalov·G. Brunthaler·A. Prinz·G. Bauer·B. I. Fouks
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Abstract

We have found that the conduction in Si-MOS structures has a substantial imaginary component in the metallic phase for the density range 6 \times n_c > n > n_c, where n_c is the critical density of the metal-insulator transition. For high mobility samples, the corresponding delay (or advance) time equals approximately to 0.1 - 10ms and increases exponentially as density and temperature decrease. In very low mobility samples, at temperature of 0.3K, the time-lag in establishing the equilibrium resistance reaches hundreds of seconds. The delay (advance) times are approximately 10^2-10^8 times larger than the overall RC-time of the gated structure. These results give evidence for a non-Boltzmann character of the transport in the low-density metallic phase. We relate the time-dependent effects to tunneling of carries between the 2D bulk and localized states.

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V. M. Pudalov, G. Brunthaler, A. Prinz, G. Bauer, B. I. Fouks. 1999-07-26. Time-dependent Effects in the Metallic Phase in Si-MOS: Evidence for Non-Diffusive Transport. https://arxiv.org/abs/cond-mat/9907401

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