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arXiv · 2110.12355

Benchmarking Information Scrambling

Joseph Harris·Bin Yan·Nikolai A. Sinitsyn
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Abstract

Information scrambling refers to the rapid spreading of initially localized information over an entire system, via the generation of global entanglement. This effect is usually detected by measuring a temporal decay of the out-of-time order correlators. However, in experiments, decays of these correlators suffer from fake positive signals from various sources, e.g., decoherence due to inevitable couplings to the environment, or errors that cause mismatches between the purported forward and backward evolutions. In this work, we provide a simple and robust approach to single out the effect of genuine scrambling. This allows us to benchmark the scrambling process by quantifying the degree of the scrambling from the noisy backgrounds.

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Joseph Harris, Bin Yan, Nikolai A. Sinitsyn. 2021-10-24. Benchmarking Information Scrambling. https://doi.org/10.1103/physrevlett.129.050602

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