Spin orbital singlet formation and fluctuations in the Cluster Mott Insulator GaTa4Se8

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.

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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