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arXiv · 2001.02176

Quantum information scrambling in a trapped-ion quantum simulator with tunable range interactions

Manoj K. Joshi·Andreas Elben·Benoît Vermersch·Tiff Brydges·Christine Maier·Peter Zoller·Rainer Blatt·Christian F. Roos
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Abstract

In ergodic many-body quantum systems, locally encoded quantum information becomes, in the course of time evolution, inaccessible to local measurements. This concept of "scrambling" is currently of intense research interest, entailing a deep understanding of many-body dynamics such as the processes of chaos and thermalization. Here, we present first experimental demonstrations of quantum information scrambling on a 10-qubit trapped-ion quantum simulator representing a tunable long-range interacting spin system, by estimating out-of-time ordered correlators (OTOCs) through randomized measurements. We also analyze the role of decoherence in our system by comparing our measurements to numerical simulations and by measuring R\'enyi entanglement entropies.

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Manoj K. Joshi, Andreas Elben, Benoît Vermersch, Tiff Brydges, Christine Maier, Peter Zoller, Rainer Blatt, Christian F. Roos. 2020-01-07. Quantum information scrambling in a trapped-ion quantum simulator with tunable range interactions. https://doi.org/10.1103/physrevlett.124.240505

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