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arXiv · 2301.05428

Experimental Observation of Topological Quantum Criticality

Sonja Barkhofen·Syamsundar De·Jan Sperling·Christine Silberhorn·Alexander Altland·Dmitry Bagrets·Kun Woo Kim·Tobias Micklitz
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Abstract

We report on the observation of quantum criticality forming at the transition point between topological Anderson insulator phases in a one-dimensional photonic quantum walk with spin. The walker's probability distribution reveals a time-staggered profile of the dynamical spin-susceptibility, recently suggested as a smoking gun signature for topological Anderson criticality in the chiral symmetry class AIII. Controlled breaking of phase coherence removes the signal, revealing its origin in quantum coherence.

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Sonja Barkhofen, Syamsundar De, Jan Sperling, Christine Silberhorn, Alexander Altland, Dmitry Bagrets, Kun Woo Kim, Tobias Micklitz. 2023-01-13. Experimental Observation of Topological Quantum Criticality. https://arxiv.org/abs/2301.05428

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