论文信息 - Effects of interactions and disorder on the compressibility of two‐dimensional electron and hole systems

Effects of interactions and disorder on the compressibility of two‐dimensional electron and hole systems

We have studied the thermodynamic compressibility of 2D electron and 2D hole gases near the apparent metal-insulator transition, in the ranges of the interaction parameter rs =1–2.5 and rs =10–30, respectively. Nonmonotonic dependence of the inverse compressibility on the carrier density is observed with an upturn at low densities. Despite the large difference in rs , this behaviour of inverse compressibility in both electron and hole systems can be quantitatively accounted for by a nonlinear screening of disorder by the carriers, in particular, by the disorder-driven proliferation of depletion regions in the 2D channel. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

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