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Quantum geometrical effects in non-Hermitian systems

Anton Montag1,2,3,* and Tomoki Ozawa1,†

  • *Contact author: anton.montag@mpl.mpg.de
  • †Contact author: tomoki.ozawa.d8@tohoku.ac.jp
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Phys. Rev. Research 8, 013181 – Published 19 February, 2026

DOI: https://doi.org/10.1103/qb8s-9c6y

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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Phys. Rev. Research 8, 013181– Published 19 February, 2026
  • Received 8 December 2025
  • Accepted 21 January 2026
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