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DOE OSTI · 2397458

Magnon gap tuning in lithium-doped MnTe

Yumnam, George·Moseley, Duncan H.·Paddison, Joseph M.·Suggs, Christiana Z.·Zappala, Emma·Parker, David S.·Granroth, Garrett E.·Morris, Gerald D.·Polash, Md Hossain·Vashaee, Daryoosh·McGuire, Michael A.·Zhao, Huaizhou·Manley, Michael E.·Frandsen, Benjamin A.·Hermann, Raphaël P.
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Abstract

Manganese telluride (MnTe) is a prospective platform for ultrafast carrier dynamics, spin-based thermoelectrics, and magnon-drag transport due to its unique electronic and magnetic properties. We use inelastic neutron scattering to study both pure and lithium-doped MnTe, focusing on the influence of doping in opening a magnon gap. We use neutron powder diffraction to determine critical exponents for the phase transition in both pure and Li-doped MnTe and complement this information with muon spin rotation/relaxation. In conclusion, the opening of the magnon gap and spin reorientation in Li-doped MnTe is mainly due to increased magnetic anisotropy along the [001] axis, a feature not present in pure MnTe.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYantiferromagnetismdensity functional theoryexchange interactionfirst-principles calculationsinelastic neutron scatteringlinear spin wave theorymagnetic anisotropymagnons

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Yumnam, George, Moseley, Duncan H., Paddison, Joseph M., Suggs, Christiana Z., Zappala, Emma, Parker, David S., Granroth, Garrett E., Morris, Gerald D., Polash, Md Hossain, Vashaee, Daryoosh, McGuire, Michael A., Zhao, Huaizhou, Manley, Michael E., Frandsen, Benjamin A., Hermann, Raphaël P.. 2024-06-24. Magnon gap tuning in lithium-doped MnTe. https://doi.org/10.1103/physrevb.109.214434

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