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arXiv · 2605.10329

Partial Quantisation of Non-Hermitian Berry Phases in Time-Varying Media

Calvin Hooper
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Abstract

A fundamental symmetry of the non-Hermitian operators describing wave-propagation in time-varying media imbue such systems with non-trivial topology. This topology may be measured directly in a wide range of experimental settings as a quantised real part of the Berry phase, contrasting unconstrained geometric gain or loss. This topological index is provided explicitly for practical examples, including a non-Hermitian analogue of the Su-Schrieffer-Heeger model.

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Calvin Hooper. 2026-05-11. Partial Quantisation of Non-Hermitian Berry Phases in Time-Varying Media. https://arxiv.org/abs/2605.10329

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