Two-dimensional non-Hermitian delocalization transition as a probe for thelocalization length - art. no. 201321

When one applies a type of non-Hermitian effect, constant imaginary vector potential. to disordered systems, delocalization is induced even in two or lower dimensions. By using the non-Hermitian induced transition as a probe, we propose a procedure of estimating localization in arbitrary-dimensional systems. By examining numerically the two-dimensional non-Hermitian tight- binding model with onsite disorder, it is shown that the failure of absorbi ng the non-Hermitian effect, namely the breakdown of the imaginary gauge tr ansformation, characterize the inverse localization length near the band ce nter.