Effect of Quenched Disorder on a Spin-1/2 Triangular-Lattice Antiferromagnet Ba2.8Sr0.2CoSb2O9

ORAL

Abstract

The novel up-up-down (UUD) ground state, which has been predicted to be stabilized by quantum fluctuations only, is a good example of exotic magnetism in the triangular-lattice antiferromagnet (TAF). This quantum UUD state, which manifests itself with a constant magnetization (1/3 of the saturation magnetization) over a finite field range, has been reported in the S=1/2 TAF Ba3CoSb2O9. Recently, we present a systematic study on the effect of quenched disorder on Ba2.8Sr0.2CoSb2O9 using DC and AC susceptibilities and advanced neutron scattering. DC susceptibility at zero field confirms an antiferromagnetic ordering below 2.8 K with an easy-plane anisotropy in Ba2.8Sr0.2CoSb2O9. And AC susceptibility measurement suggests that the field extent for the UUD phase of Ba2.8Sr0.2CoSb2O9 is larger than that of Ba3CoSb2O9. We also report the neutron-scattering study on the evolution of the ordering temperature and magnetic structure as a function of applied magnetic field.

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Presenters

  • Qing Huang

    Physics and Astronomy, Univ of Tennessee, Knoxville

Authors

  • Qing Huang

    Physics and Astronomy, Univ of Tennessee, Knoxville

  • Haidong Zhou

    Physics and Astronomy, Univ of Tennessee, Knoxville, Physics and Astronomy, University of Tennessee Knoxville, Department of Physics and Astronomy, University of Tennessee, Department of Physics and Astronomy, University of Tennessee Knoxville, Department of Physics & Astronomy, University of Tennessee, University of Tennessee, Physics and Astronomy, University of Tennessee, Physics, University of Tennessee, Univ of Tennessee, Knoxville, Physics and Astronomy, University of Tennessee, knoxville, Dept. of Physics and Astronomy, University of Tennessee

  • Jie Ma

    Physics and Astronomy, Shanghai Jiao Tong University, Shanghai Jiao Tong Univ

  • Eun Choi

    National High Magnetic Field Laboratory, NHMFL

  • Zhilun Lu

    Helmholtz-Zentrum Berlin für Materialien und Energie GmbH

  • Tao Hong

    Neutron Scattering Division, Oak Ridge National Laboratory, Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge National Lab, Oak Ridge National Laboratory, Neutron scattering devision, Oak Ridge National Lab