Thermodynamic density of states of two-dimensional GaAs systems near the apparent metal-insulator transition |
| |
Authors: | Allison G Galaktionov E A Savchenko A K Safonov S S Fogler M M Simmons M Y Ritchie D A |
| |
Affiliation: | School of Physics, University of Exeter, Exeter EX4 4QL, United Kingdom. |
| |
Abstract: | 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. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|