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Two-dimensional Non-Hermitian Delocalization Transition as a Probe for the Localization Length

Tsunenao Kuwae·Nobuhiko Taniguchi
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Abstract

When one applies a type of non-Hermitian effect, constant imaginary vector potential, to disordered systems, delocalization is induced even in two or lower dimension. By using the non-Hermitian induced transition as a probe, We propose a new procedure of estimating localization in arbitrary-dimensional systems. By examining numerically the two-dimensional non-Hermitian tight-biding model with onsite disorder, it is shown that the failure of absorbing the non-Hermitian effect, namely the breakdown of the imaginary gauge transformation, characterize the inverse localization length near the band center.

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Tsunenao Kuwae, Nobuhiko Taniguchi. 2001-11-21. Two-dimensional Non-Hermitian Delocalization Transition as a Probe for the Localization Length. https://doi.org/10.1103/physrevb.64.201321

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