Spin Effects Making zT > 1

ORAL

Abstract

Recent studies of thermoelectric properties of the antiferromagnetic MnTe:Li have revealed the existence of a strong spin effect that extends across a broad range of temperature leading to zT>1 [1,2]. While carrier mobility and heat capacity were strongly affected by spin contributions near the Neel temperature, TN=307K, the thermopower demonstrated robust spin effects extending up to 900K. Spin contribution to those properties below TN has been attributed to the magnon-drag effect [3]. A recent study [2] attributed the thermopower enhancement to paramagnon-drag effect originated from the mid or short-range magnetic ordering above TN. Neutron scattering study showed an agreement to that theory to some extent while some competing theories such as the spin-fluctuations and spin entropy can also explain thermopower enhancement in magnetic materials [1,4]. The objective of this work is to show the agreements and disagreements of different spin-based theories in describing the transport properties of MnTe:Li and to compare similar material systems to gain better insight to the underlying physics.
[1] Vashaee, D., et al., Spin-Cal. IX, June 2018
[2] Yuanhua, Z., et al., Am. Phys. Soc., March 2018
[3] Wasscher, J. D., Phys. Lett. 8, 302-304,1964
[4] Gratz, E., Physica B 237-238, 1997

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Presenters

  • Daryoosh Vashaee

    • Department of Electrical and Computer Engineering, North Carolina State University
    • North Carolina State University

Authors

  • Daryoosh Vashaee

    • Department of Electrical and Computer Engineering, North Carolina State University
    • North Carolina State University

  • Md Mobarak Hossain Polash

    • Department of Materials Science and Engineering, North Carolina State University
    • North Carolina State University

  • Vladislav Perelygin

    • Department of Chemistry, North Carolina State University

  • Morteza Rasoulianboroujeni

    • Department of Developmental Science, Marquette University
    • North Carolina State University

  • Yuanhua Zheng

    • Department of Mechanical and Aerospace Engineering, The Ohio State University
    • Ohio State University

  • Tianqi Lu

    • Chinese Academy of Sciences, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics
    • Institute of Physics, Chinese Academy of Sciences

  • Ning Liu

    • Chinese Academy of Sciences, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics
    • Institute of Physics, Chinese Academy of Sciences

  • Michael Manley

    • Materials Science and Technology Division, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory
    • Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge TN-37831-6064, USA

  • Raphael Hermann

    • Oak Ridge National Laboratory
    • Materials Science and Technology Division, Oak Ridge National Laboratory
    • Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge TN-37831-6064, USA

  • Alex I Smirnov

    • Department of Chemistry, North Carolina State University
    • North Carolina State University

  • Joseph P C Heremans

    • Department of Mechanical and Aerospace Engineering, The Ohio State University
    • Ohio State University
    • Ohio State Univ - Columbus
    • Department of Mechanical Engineering, The Ohio State University
    • Department of Mechanical and Aerospace Engineering, Department of Physics, Department of Materials Science and Engineering, The Ohio State University, Columbus, OH 43210, USA

  • Huaizhou Zhao

    • Institute of Physics, Chinese Academy of Sciences
    • Chinese Academy of Sciences, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics
    • Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China