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arXiv · 0710.3542

Transport and percolation in a low-density high-mobility two-dimensional hole system

M. J. Manfra·E. H. Hwang·S. Das Sarma·L. N. Pfeiffer·K. W. West·A. M. Sergent
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Abstract

We present a study of the temperature and density dependence of the resistivity of an extremely high quality two-dimensional hole system grown on the (100) surface of GaAs. For high densities in the metallic regime ($p\agt 4 \times 10^{9}$ cm$^{-2}$), the nonmonotonic temperature dependence ($\sim 50-300$ mK) of the resistivity is consistent with temperature dependent screening of residual impurities. At a fixed temperature of $T$= 50 mK, the conductivity vs. density data indicates an inhomogeneity driven percolation-type transition to an insulating state at a critical density of $3.8\times 10^9$ cm$^{-2}$.

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M. J. Manfra, E. H. Hwang, S. Das Sarma, L. N. Pfeiffer, K. W. West, A. M. Sergent. 2007-10-18. Transport and percolation in a low-density high-mobility two-dimensional hole system. https://doi.org/10.1103/physrevlett.99.236402

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