The Anderson metal-insulator transition in the presence of scale-free disorderM. L. Ndawana1, R. A. Römer1 and M. Schreiber2
1 Department of Physics and Centre for Scientific Computing, University of Warwick Coventry, CV4 7AL, UK
2 Institut für Physik, Technische Universität Chemnitz - 09107 Chemnitz, Germany
received 27 April 2004; accepted in final form 8 October 2004
published online 5 November 2004
We investigate the three-dimensional Anderson model of localization via a modified transfer matrix method in the presence of scale-free diagonal disorder characterized by a disorder correlation function g(r) decaying asymptotically as . We study the dependence of the localization length exponent on the correlation strength exponent . For fixed disorder W, there is a critical , such that for , and for , remains that of the uncorrelated system in accordance with the extended Harris criterion. At the band center, is independent of but equal to that of the uncorrelated system. The physical mechanisms leading to this different behavior are discussed.
71.30.+h - Metal-insulator transitions and other electronic transitions.
72.10.Bg - General formulation of transport theory.
72.15.Rn - Localization effects (Anderson or weak localization).
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