Related papers: Observation of non-Hermitian bulk-boundary correspondence in non-chiral non-unitary quantum dynamics of single photons

Observation of non-Hermitian bulk-boundary correspondence in non-chiral non-unitary quantum dynamics of single photons

URL: http://arxiv.org/abs/2504.04882v1
Date: Mon, 07 Apr 2025 09:43:43 GMT
Title: Observation of non-Hermitian bulk-boundary correspondence in non-chiral non-unitary quantum dynamics of single photons
Authors: Miao Zhang, Yue Zhang, Shuai Li, Rui Tian, Tianhao Wu, Yingchao Xu, Yi-an Li, Yuanbang Wei, Hong Gao, M. Suhail Zubairy, Fuli Li, Bo Liu,
Abstract summary: In non-Hermitian systems, preserved chiral symmetry is one of the key ingredients, which plays a pivotal role in determining non-Hermitian topology.<n>We theoretically predict and experimentally demonstrate the bulk-boundary correspondence of a one-dimensional (1D) non-Hermitian system with chiral symmetry breaking.
Score: 31.05848822220465
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Abstract: The breakdown of conventional bulk-boundary correspondence, a cornerstone of topological physics, is one of counter-intuitive phenomena in non-Hermitian systems, that is deeply rooted in symmetry. In particular, preserved chiral symmetry is one of the key ingredients, which plays a pivotal role in determining non-Hermitian topology. Nevertheless, chiral symmetry breaking in non-Hermitian systems disrupts topological protection, modifies topological invariants, and substantially reshapes spectral and edge-state behavior. The corresponding fundamentally important bulk-boundary correspondence thus needs to be drastically reconstructed. However, it has so far eluded experimental efforts. Here, we theoretically predict and experimentally demonstrate the bulk-boundary correspondence of a one-dimensional (1D) non-Hermitian system with chiral symmetry breaking in discrete-time non-chiral non-unitary quantum walks of single photons. Through constructing a domain-wall configuration, we experimentally observe the photon localization at the interface of domain-wall structure, clearly indicating the presence of the topological edge mode. The appearance of that matches excellently with the prediction of our introduced non-chiral non-Bloch topological invariants pair. Our work thus unequivocally builds the non-Hermitian bulk-boundary correspondence as a general principle for studying topological physics in non-Hermitian systems with chiral symmetry breaking.

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