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arXiv · 2408.12645

Probing topological entanglement on large scales

Robert Ott·Torsten V. Zache·Nishad Maskara·Mikhail D. Lukin·Peter Zoller·Hannes Pichler
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Abstract

Topologically ordered quantum matter exhibits intriguing long-range patterns of entanglement, which reveal themselves in subsystem entropies. However, measuring such entropies, which can be used to certify topological order, on large partitions is challenging and becomes practically unfeasible for large systems. We propose a protocol based on local adiabatic deformations of the Hamiltonian which extracts the universal features of long-range topological entanglement from measurements on small subsystems of finite size, trading an exponential number of measurements against a polynomial-time evolution. Our protocol is general and readily applicable to various quantum simulation architectures. We apply our method to various string-net models representing both abelian and non-abelian topologically ordered phases, and illustrate its application to neutral atom tweezer arrays with numerical simulations.

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Robert Ott, Torsten V. Zache, Nishad Maskara, Mikhail D. Lukin, Peter Zoller, Hannes Pichler. 2024-08-22. Probing topological entanglement on large scales. https://arxiv.org/abs/2408.12645

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