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arXiv · 1801.00999

Unitary $n$-designs via random quenches in atomic Hubbard and Spin models: Application to the measurement of R\'enyi entropies

B. Vermersch·A. Elben·M. Dalmonte·J. I. Cirac·P. Zoller
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Abstract

We present a general framework for the generation of random unitaries based on random quenches in atomic Hubbard and spin models, forming approximate unitary $n$-designs, and their application to the measurement of R\'enyi entropies. We generalize our protocol presented in [Elben2017: arXiv:1709.05060, to appear in Phys. Rev. Lett.] to a broad class of atomic and spin lattice models. We further present an in-depth numerical and analytical study of experimental imperfections, including the effect of decoherence and statistical errors, and discuss connections of our approach with many-body quantum chaos.

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B. Vermersch, A. Elben, M. Dalmonte, J. I. Cirac, P. Zoller. 2018-01-03. Unitary $n$-designs via random quenches in atomic Hubbard and Spin models: Application to the measurement of R\'enyi entropies. https://doi.org/10.1103/physreva.97.023604

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