Delocalization and ballistic dynamics in the two-dimensional Anderson model with long-range correlated disorderF. A. B. F. de Moura1, 2, M. D. Coutinho-Filho1, M. L. Lyra2 and E. P. Raposo1
1 Laboratório de Física Teórica e Computacional, Departamento de Física Universidade Federal de Pernambuco - 50670-901 Recife, PE, Brazil
2 Departamento de Física, Universidade Federal de Alagoas Maceió AL 57072-970, Brazil
(Received 18 November 2003; accepted in final form 17 March 2004)
We study the nature of one-electron eigenstates in a two-dimensional ( 2d) Anderson model with long-range correlated disorder. Long-range correlations are introduced by using a 2d discrete Fourier method which generates an appropriated disorder distribution with spectral density . Our numerical data suggest that the exponents governing the collapse of the participation function for low energies ( ) and the long time decay of the autocorrelation function ( ) satisfy the scaling relation . They also imply that the system exhibits a crossover from a diffusive spread for weakly correlated disorder to a ballistic dynamics associated with the emergence of extended states in the strongly correlated disorder regime .
78.30.Ly - Disordered solids.
71.30.+h - Metal-insulator transitions and other electronic transitions.
73.20.Jc - Delocalization processes.
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