Dynamics, Entanglement, and the Classical Point in the Transverse-Field XXZ Chain Cs<sub>2</sub>CoCl<sub>4</sub>

ORAL

Abstract

We investigate the quantum phase transition in the S=1/2 transverse-field XXZ spin chain using multiple entanglement measures and witnesses. As the field strength increases, this system passes through two quantum critical points of different universality classes, as well as a classical point. Consequently, the entanglement can be tuned by simply changing the magnetic field. Using DMRG calculations we study the entanglement entropy, one-tangle, two-tangle, and quantum Fisher information. We also report high-resolution inelastic neutron scattering data on Cs2CoCl4, and the experimental extraction of entanglement witnesses from the neutron data. We find that quantum Fisher information values extracted from experiment and simulation show good agreement, demonstrating it is an experimentally viable probe of entanglement.

*This work was supported by the Scientific Discovery through Advanced Computing (SciDAC) program funded by U.S. Department of Energy, Office of Science, Advanced Scientific Computing Research and Basic Energy Sciences, Division of Materials Sciences and Engineering.

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Presenters

  • Pontus Laurell

    • Oak Ridge National Lab

Authors

  • Pontus Laurell

    • Oak Ridge National Lab

  • Allen Scheie

    • Oak Ridge National Lab

  • Chiron J. Mukherjee

    • Clarendon Laboratory, Oxford University

  • Michael M. Koza

    • Institut Laue-Langevin

  • Mechthild Enderle

    • Institut Laue-Langevin

  • Zbigniew Tylczynski

    • Faculty of Physics, Adam Mickiewicz University

  • Satoshi Okamoto

    • Oak Ridge National Lab
    • Materials Science and Technology Division, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory

  • Radu Coldea

    • University of Oxford
    • Clarendon Laboratory, University of Oxford
    • Clarendon Laboratory, Oxford University

  • David A Tennant

    • Oak Ridge National Lab
    • Oak Ridge National Laboratory

  • Gonzalo Alvarez

    • Oak Ridge National Lab
    • Oak Ridge National Laboratory
    • Computational Sciences and Engineering Division, Oak Ridge National Laboratory
    • Center for Nanophase Materials Sciences, Oak Ridge National Laboratory
    • Computational Sciences & Engineering Division and Center for Nanophase Materials Sciences, Oak Ridge National Laboratory
    • Computational Sciences and Engineering Division and Center for Nanophase Materials Sciences, Oak Ridge National Laboratory