Scrambling and complexity in phase space

ORAL

Abstract

In this talk, we will describe extensions of the study of scrambling and complexity to infinite-dimensional continuous variable (CV) systems. Unlike their discrete variable (DV) cousins, continuous variable systems exhibit two complementary domains of information scrambling: 1) scrambling in the phase space of a single mode and 2) scrambling across multiple modes. Moreover, for each of these domains, we identify two distinct "types" of scrambling; strict scrambling, where an initial operator localized in phase space spreads out and quasi-scrambling, where a local ensemble of operators distorts but the overall phase space volume remains fixed. To characterize these behaviors, we introduce a CV out-of-time-order correlator (OTOC) based upon displacement operators, which can be experimentally measured. By studying operator spreading and entanglement formation in a random local Gaussian circuit ensemble, we infer the dynamics of generic, chaotic, locally-interacting systems.Our work opens the door to experimentally probing phase space scrambling in CV systems, including cavity QED and quantum optics architectures.

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Presenters

  • Quntao Zhuang

    Physics, University of California, Berkeley, Department of Physics, University of California, Berkeley, California 94720, USA, University of California, Berkeley

Authors

  • Quntao Zhuang

    Physics, University of California, Berkeley, Department of Physics, University of California, Berkeley, California 94720, USA, University of California, Berkeley

  • Thomas Schuster

    Department of Physics, University of California, Berkeley, California 94720, USA, University of California, Berkeley

  • Beni Yoshida

    Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5, Canada, Perimeter Institute for Theoretical Physics

  • Norman Yao

    University of California, Berkeley, Department of Physics, University of California, Berkeley, California 94720, USA, Physics, University of California, Berkeley, Department of Physics, University of California, Berkeley, University of California, Berkeley and Lawrence Berkeley National Laboratory, Materials Sciences Division