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Critical properties of the metal-insulator transition in anisotropic systems

Frank Milde·Rudolf A. Römer·Michael Schreiber·Ville Uski
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Abstract

We study the three-dimensional Anderson model of localization with anisotropic hopping, i.e., weakly coupled chains and weakly coupled planes. In our extensive numerical study we identify and characterize the metal-insulator transition by means of the transfer-matrix method. The values of the critical disorder $W_c$ obtained are consistent with results of previous studies, including multifractal analysis of the wave functions and energy level statistics. $W_c$ decreases from its isotropic value with a power law as a function of anisotropy. Using high accuracy data for large system sizes we estimate the critical exponent as $ν=1.62\pm0.07$. This is in agreement with its value in the isotropic case and in other models of the orthogonal universality class.

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Frank Milde, Rudolf A. Römer, Michael Schreiber, Ville Uski. 1999-11-03. Critical properties of the metal-insulator transition in anisotropic systems. https://doi.org/10.1007/s100510051173

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