2006/03/22 by Giles Allison, G. D. Allison, E. A. Galaktionov +6
Physics and Astronomy · #Quantum and electron transport phenomena #Semiconductor Quantum Structures and Devices #Surface and Thin Film Phenomena #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.96.216407
published as Phys. Rev. Lett. 96, 216407 (2006)
arxiv created 2006/03/22 · openalex publication_date 2006/06/02 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We perform combined resistivity and compressibility studies of two-dimensional hole and electron systems which show the apparent metal-insulator transition--a crossover in the sign of deltaR/deltaT with changing density. No thermodynamic anomalies have been detected in the crossover region. Instead, despite a tenfold difference in r(s), the compressibility of both electrons and holes is well described by the theory of nonlinear screening of the random potential. We show that the resistivity exhibits a scaling behavior near the percolation threshold found from analysis of the compressibility. Notably, the percolation transition occurs at a much lower density than the crossover.