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arXiv · cond-mat/0207480

The metal-insulator transition in 2D systems at T = 0: one-particle approach

Abstract

The conductance of a disordered finite-size electron system is calculated by reducing the initial dynamic problem of arbitrary dimensionality to strictly one-dimensional problems for one-particle mode propagators. The metallic ground state of a two-dimensional conductor, which is considered as a limiting case of the actually three-dimensional quantum waveguide, is shown to result from its multi-modeness. On lowering the waveguide thickness, in practice, e.g., due to application of the ``pressing'' potential (depletion voltage), the electron system undergoes a set of continuous phase transitions connected with the discrete change in the number of extended modes. The closing of the last current-carrying mode is interpreted as the electron system transition from metallic to dielectric state. The results obtained agree qualitatively with the observed ``anomalies'' of the resistance of different electron and hole systems.

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BibTeXRIS

Yu. V. Tarasov. 2002-07-19. The metal-insulator transition in 2D systems at T = 0: one-particle approach. https://doi.org/10.1063/1.1542377

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