Understanding the Short-Range Magnetic Correlations in MnTe Through Magnetic Pair Distribution Function Analysis

ORAL

Abstract

The antiferromagnetic semiconductor MnTe has attracted attention as both a high-performance thermoelectric and a candidate material for spintronics. The magnetic properties of MnTe play a crucial role in these applications. MnTe has a hexagonal layered structure in which magnetic Mn2$+$ spins order ferromagnetically within the plane and antiferromagnetically between planes below T$_{\mathrm{N}}=$ 307 K. Above T$_{\mathrm{N}}$, robust short-range magnetic correlations survive to high temperature. These correlations are a significant contributor to the high thermoelectric figure of merit zT in MnTe through a mechanism known as paramagnon drag. We present comprehensive atomic and magnetic pair distribution function (PDF) analysis of neutron total scattering data collected from pure and doped MnTe powders, together with three-dimensional magnetic PDF data obtained from a single crystal of MnTe. These complementary data sets allow us to track the evolution of magnetic correlations from the long-range ordered state at low temperature to the short-range ordered state at high temperature. We present real-space magnetic models that reproduce the mPDF patterns with quantitative accuracy and discuss these results in the context of existing work on MnTe.

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Authors

  • Jacob Christensen

    Brigham Young University

  • Benjamin Frandsen

    Brigham Young University

  • Rupjyoti Gogoi

    Arizona State University, Colorado State University, University of Utah, Utah State University, George Mason University, Brigham Young University, University of Colorado, Boulder, Georgia Institute of Technology, University of Colorado, Boulder; North China Electric Power University, Argonne National Laboratory, Carnegie Mellon University, Purdue University, Yunnan University, University of Arizona, Ball Aerospace, Ponderosa Associates Limited, Polsinelli PC, Saleh Research Centre, New Mexico State University, Oak Ridge National Laboratory, Center for Memory and Recording research, Advanced Photon Source, Chemnitz university of technology, Tezpur University

  • Rupjyoti Gogoi

    Arizona State University, Colorado State University, University of Utah, Utah State University, George Mason University, Brigham Young University, University of Colorado, Boulder, Georgia Institute of Technology, University of Colorado, Boulder; North China Electric Power University, Argonne National Laboratory, Carnegie Mellon University, Purdue University, Yunnan University, University of Arizona, Ball Aerospace, Ponderosa Associates Limited, Polsinelli PC, Saleh Research Centre, New Mexico State University, Oak Ridge National Laboratory, Center for Memory and Recording research, Advanced Photon Source, Chemnitz university of technology, Tezpur University