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arXiv · 1607.01801

Interferometric Approach to Probing Fast Scrambling

Norman Y. Yao·Fabian Grusdt·Brian Swingle·Mikhail D. Lukin·Dan M. Stamper-Kurn·Joel E. Moore·Eugene A. Demler
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Abstract

Out-of-time-order correlation functions provide a proxy for diagnosing chaos in quantum systems. We propose and analyze an interferometric scheme for their measurement, using only local quantum control and no reverse time evolution. Our approach utilizes a combination of Ramsey interferometry and the recently demonstrated ability to directly measure Renyi entropies. To implement our scheme, we present a pair of cold-atom-based experimental blueprints; moreover, we demonstrate that within these systems, one can naturally realize the transverse-field Sherrington-Kirkpatrick (TFSK) model, which exhibits certain similarities with fast scrambling black holes. We perform a detailed numerical study of scrambling in the TFSK model, observing an interesting interplay between the fast scrambling bound and the onset of spin-glass order.

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Norman Y. Yao, Fabian Grusdt, Brian Swingle, Mikhail D. Lukin, Dan M. Stamper-Kurn, Joel E. Moore, Eugene A. Demler. 2016-07-06. Interferometric Approach to Probing Fast Scrambling. https://arxiv.org/abs/1607.01801

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