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2D Lattice of coupled Sinai billiards: metal or insulator at g<<1

M. V. Budantsev·Z. D. Kvon·A. G. Pogosov·G. M. Gusev·J. C. Portal·D. K. Maude·N. T. Moshegov·A. I. Toropov
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Abstract

We investigate the transport in a two-dimensional (2D) lattice of coupled Sinai billiards fabricated on the basis of a high-mobility 2D electron gas in GaAs/AlGaAs heterojunction. For the states with low reduced conductivity g<<1 an anomalously weak temperature dependence of g was found. The large negative magnetoresistance described by the Lorentz line-shape of the width corresponding to the half magnetic flux quantum through the area of the billiard is observed. In going from g>1 to g<<1 it strongly increases. The Shubnikov-de Haas oscillations and commensurability magnetoresistance peak are preserved at g<<1. The data suggest that the system studied behaves more like a metal than an insulator at g<<1 and is not described by the generally accepted picture of Anderson localization.

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M. V. Budantsev, Z. D. Kvon, A. G. Pogosov, G. M. Gusev, J. C. Portal, D. K. Maude, N. T. Moshegov, A. I. Toropov. 1998-02-18. 2D Lattice of coupled Sinai billiards: metal or insulator at g<<1. https://arxiv.org/abs/cond-mat/9802188

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