Spin orbital singlet formation and fluctuations in the Cluster Mott Insulator GaTa<sub>4</sub>Se<sub>8</sub>

ORAL

Abstract

The magnetism in spin-orbit Mott insulators is closely related to the interplay between electronic correlations and spin-orbit couplings which often give rise to novel quantum phases of matter. In the Lacunar spinel GaTa4Se8, electronic correlations localize a single unpaired electron on tetrahedral clusters of Ta ions, while spin-orbit coupling generates Jeff=3/2 magnetic degrees of freedom. At T=50 K, GaTa4Se8 undergoes a magnetic transition accompanied by a structural dimerization. The magnetic ground states are entangled to the lattice distortion and a preceding phonon mode was observed by neutron scattering measurements. However, the mechanism of this preceding phonon mode is still unclear. In this presentation, I will present our crystallographic results following a series of neutron scattering measurements which provide more insights to the correlations between lattice and spin-orbital jeff=3/2 states in cluster spin-orbit Mott insulator.

*This material is based upon work supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Award Number DE-SC0021223.

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Presenters

  • Tsung-Han Yang

    • Brown University

Authors

  • Tsung-Han Yang

    • Brown University

  • Tomoya Higo

    • Univ of Tokyo
    • The Institute for Solid State physics, The Univeristy of Tokyo
    • University of Tokyo

  • Shinya Kawamoto

    • The Institute for Solid State physics, The Univeristy of Tokyo

  • Satoru Nakatsuji

    • Department of Physics and ISSP, University of Tokyo
    • Department of Physics, the University of Tokyo
    • Univ of Tokyo
    • Institute for Solid State Physics, University of Tokyo
    • The Institute for Solid State physics, The Univeristy of Tokyo
    • The Institute for Solid State Physics, The University of Tokyo
    • Institute for Solid State physics, University of Tokyo

  • Kemp Plumb

    • Brown University