Antiferromagnetic magnon gap opening and spin-reorientation in Li-doped MnTe

ORAL

Abstract

MnTe emerges as a promising platform for ultra-fast carrier dynamics, spin-based thermoelectrics, and topological insulators. We investigate the impact of spin waves of a doping-driven transition of hexagonal MnTe from an easy-plane to an easy-axis antiferromagnet. Using inelastic neutron scattering, we reveal the emergence of enhanced magnetic anisotropy upon Li-doping, which leads to the opening of a magnon gap. The origin of this magnon gap in Li-doped MnTe is attributed to the enhanced c-axis magnetic anisotropy, a phenomenon absent in pure MnTe. This enhanced c-axis anisotropy in doped MnTe is also substantiated by Linear spin-wave theory and density functional theory calculations.

*This work was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division under contract no. DE-AC05-00OR22725. Portions of this research used resources at the Spallation Neutron Source and High Flux Isotope Reactor, which is a U.S. DOE Office of Science User Facility operated by the Oak Ridge National Laboratory.

–

Presenters

  • George Yumnam

    • Oak Ridge National Laboratory

Authors

  • George Yumnam

    • Oak Ridge National Laboratory

  • Duncan H Moseley

    • Oak Ridge National Lab

  • Joseph Paddison

    • Oak Ridge National Lab

  • Md Mobarak Hossain Polash

    • North Carolina State University

  • Daryoosh Vashaee

    • North Carolina State U

  • Garrett E Granroth

    • Oak Ridge National Lab
    • ORNL

  • Christiana Z Suggs

    • Department of Physics and Astronomy, Brigham Young University, Provo, UT 84602

  • Emma M Zappala

    • Brigham Young University

  • David S Parker

    • Oak Ridge National Laboratory

  • Michael E Manley

    • Oak Ridge National Lab

  • Benjamin A Frandsen

    • Brigham Young University

  • Raphael P Hermann

    • Oak Ridge National Laboratory
    • Oak Ridge National Lab
    • Oak Ridge