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Divergences of the localization lengths in the two- dimensional, off-diagonal Anderson model on bipartite lattices

Andrzej Eilmes·Rudolf A. Roemer
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Abstract

We investigate the scaling properties of the two-dimensional (2D) Anderson model of localization with purely off-diagonal disorder (random hopping). Using the transfer-matrix method and finite-size scaling we compute the infinite-size localization lengths for bipartite square and hexagonal 2D lattices, non-bipartite triangular lattices and different distribution functions for the hopping elements. We show that for small energies the localization lengths in the bipartite case diverge with a power-law behavior. The corresponding exponents are in the range $0.2 - 0.6$ and seem to depend on the type and the strength of disorder.

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Andrzej Eilmes, Rudolf A. Roemer. 2002-09-03. Divergences of the localization lengths in the two- dimensional, off-diagonal Anderson model on bipartite lattices. https://doi.org/10.1143/jpsjs.72sa.133

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