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arXiv · 0712.0716

Magnetotransport in low-density $p$-Si/SiGe heterostructures: From metal through hopping insulator to Wigner glass

I. L. Drichko·A. M. Dyakonov·I. Yu. Smirnov·A. V. Suslov·Y. M. Galperin·V. Vinokur·M. Myronov·O. A. Mironov·D. R. Leadley
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Abstract

We study DC and AC transport in low-density $p-$Si/SiGe heterostructures at low temperatures and in a broad domain of magnetic fields up to 18 T. Complex AC conductance is determined from simultaneous measurement of velocity and attenuation of a surface acoustic wave propagating in close vicinity of the 2D hole layer. The observed behaviors of DC and AC conductance are interpreted as an evolution from metallic conductance at B=0 through hopping between localized states in intermediate magnetic fields (close to the plateau of the integer quantum Hall effect corresponding to the Landau-level filling factor $ν$=1) to formation of the Wigner glass in the extreme quantum limit ($B\gtrsim 14$, $T \lesssim 0.8$ K).

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I. L. Drichko, A. M. Dyakonov, I. Yu. Smirnov, A. V. Suslov, Y. M. Galperin, V. Vinokur, M. Myronov, O. A. Mironov, D. R. Leadley. 2007-12-05. Magnetotransport in low-density $p$-Si/SiGe heterostructures: From metal through hopping insulator to Wigner glass. https://doi.org/10.1103/physrevb.77.085327

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