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arXiv · 2107.14741

Detecting non-Bloch topological invariants in quantum dynamics

Kunkun Wang·Tianyu Li·Lei Xiao·Yiwen Han·Wei Yi·Peng Xue
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Abstract

Non-Bloch topological invariants preserve the bulk-boundary correspondence in non-Hermitian topological systems, and are a key concept in the contemporary study of non-Hermitian topology. Here we report the dynamic detection of non-Bloch topological invariants in single-photon quantum walks, revealed through the biorthogonal chiral displacement, and crosschecked with the dynamic spin textures in the generalized quasimomentum-time domain following a quantum quench. Both detection schemes are robust against symmetry-preserving disorders, and yield consistent results with theoretical predictions. Our experiments are performed far away from any boundaries, and therefore underline non-Bloch topological invariants as intrinsic properties of the system that persist in the thermodynamic limit. Our work sheds new light on the experimental investigation of non-Hermitian topology.

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Kunkun Wang, Tianyu Li, Lei Xiao, Yiwen Han, Wei Yi, Peng Xue. 2021-07-30. Detecting non-Bloch topological invariants in quantum dynamics. https://doi.org/10.1103/physrevlett.127.270602

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