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arXiv · 2512.07250

Non-Hermitian Bose-Hubbard-like quantum models

Miloslav Znojil
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Abstract

Among all of the non-Hermitian large-tridiagonal-matrix quantum Hamiltonians we choose a subclass with the structure resembling the ``benchmark'' realistic Bose-Hubbard model. We demonstrate that this choice can be declared user-friendly in the sense that the underlying singular values can be specified via a ``Hermitized'' Schr\"{o}dinger-like equation. In particular, the related ``Hermitized'' Green's functions is shown given the two alternative compact and numerically efficient matrix continued fraction forms.

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Miloslav Znojil. 2025-12-08. Non-Hermitian Bose-Hubbard-like quantum models. https://doi.org/10.1088/1742-6596%2F3152%2F1%2F012023

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