A non-Hermitian analysis of strongly correlated quantum systems

Yuichi Nakamura; Naomichi Hatano

doi:10.1016/j.physb.2006.01.107

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A non-Hermitian analysis of strongly correlated quantum systems

Yuichi Nakamura·Naomichi Hatano

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Abstract

We study a non-Hermitian generalization of strongly correlated quantum systems in which the transfer energy of electrons is asymmetric. It is known that a non-Hermitian critical point is equal to the inverse localization length of a Hermitian non-interacting random electron system. We here conjecture that we can obtain in the same way the correlation length of a Hermitian interacting non-random system. We confirm the conjecture using exact solutions and numerical finite-size data of the Hubbard model and the antiferromagnetic XXZ model in one dimension.

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Yuichi Nakamura, Naomichi Hatano. 2006-03-03. A non-Hermitian analysis of strongly correlated quantum systems. https://doi.org/10.1016/j.physb.2006.01.107

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