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DOE OSTI · 1853553

Mixed-State Entanglement from Local Randomized Measurements

Elben, Andreas·Kueng, Richard·Huang, Hsin-Yuan (Robert)·van Bijnen, Rick·Kokail, Christian·Dalmonte, Marcello·Calabrese, Pasquale·Kraus, Barbara·Preskill, John·Zoller, Peter·Vermersch, Benoît
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Abstract

In this work, we propose a method for detecting bipartite entanglement in a many-body mixed state based on estimating moments of the partially transposed density matrix. The estimates are obtained by performing local random measurements on the state, followed by postprocessing using the classical shadows framework. Our method can be applied to any quantum system with single-qubit control. We provide a detailed analysis of the required number of experimental runs, and demonstrate the protocol using existing experimental data [Brydges et al., Science 364, 260 (2019)].

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1-dimensional spin chains71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSEntanglement detectionPhysicsQuantum simulationQuantum spin chainsQuasiparticles & collective excitationsXY model

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Elben, Andreas, Kueng, Richard, Huang, Hsin-Yuan (Robert), van Bijnen, Rick, Kokail, Christian, Dalmonte, Marcello, Calabrese, Pasquale, Kraus, Barbara, Preskill, John, Zoller, Peter, Vermersch, Benoît. 2020-11-11. Mixed-State Entanglement from Local Randomized Measurements. https://doi.org/10.1103/physrevlett.125.200501

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