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arXiv · 2512.07264

Quantum geometrical effects in non-Hermitian systems

Anton Montag·Tomoki Ozawa
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Abstract

We explore the relation between quantum geometry in non-Hermitian systems and physically measurable phenomena. We highlight various situations in which the behavior of a non-Hermitian system is best understood in terms of quantum geometry, namely the notion of adiabatic potentials in non-Hermitian systems and the localization of Wannier states in periodic non-Hermitian systems. Further, we show that the non-Hermitian quantum metric appears in the response of the system upon time-periodic modulation, which one can use to experimentally measure the non-Hermitian quantum metric. We validate our results by providing numerical simulations of concrete exemplary systems.

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Anton Montag, Tomoki Ozawa. 2025-12-08. Quantum geometrical effects in non-Hermitian systems. https://doi.org/10.1103/qb8s-9c6y

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