Multiferroic behavior at a spin state transition

ORAL

Abstract

We describe multiferroic behavior at a spin state transition (SST), instead of the more traditional approach using exchange-coupled order like ferromagnetism or spiral antiferromagnetism. SSTs involve large changes in ionic size, bonding and lattice, and so have potential for strong magnetoelectric coupling. We observe a magnetic field-induced electric polarization change at an SST that is within an order of magnitude of the record for any material. SSTs such as the S = 1 to S = 2 transition in Mn3+ occur when electrons change their occupation of magnetic partially-filed orbitals. SSTs can be sharp, first-order hysteretic phase transitions and they are an increasingly common functionality in inorganic-organic hybrid materials, persisting up to room temperature in some compounds. We study a Mn-based molecular system in which the high-spin state is Jahn-Teller active, and the JT distortions carry an electric dipole. We show that the magnetic field-induced SST induces ferroelectricity in both DC and pulsed magnetic fields. We use high magnetic fields at the NHMFL to study the magnetic and electric behavior of this system across a significant fraction of its T-H phase space, and compare to a phenomenological theoretical model.

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Presenters

  • Vivien Zapf

    Los Alamos National Laboratory, NHMFL, Los Alamos Natl Lab

Authors

  • Vivien Zapf

    Los Alamos National Laboratory, NHMFL, Los Alamos Natl Lab

  • Shalinee Chikara

    Auburn University, NHMFL, Los Alamos Natl Lab

  • Shizeng Lin

    Theory Div., Los Alamos Natl Lab

  • Nathan Smythe

    Chemistry Div., Los Alamos Natl Lab

  • John Singleton

    Los Alamos Natl Lab, Los Alamos National Laboratory, National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos National Lab NHMFL, NHMFL-LANL, NHMFL at Los Alamos National Lab, NHMFL, Los Alamos Natl Lab, NHMFL - Los Alamos

  • Brian Scott

    Mat Sci, Los Alamos Natl Lab

  • Elizabeth Krenkel

    Harvey Mudd College

  • Jim Eckert

    Harvey Mudd College

  • Cristian Batista

    Department of Physics and Astronomy, Univ of Tennessee, Knoxville, Univ of Tennessee, Knoxville, Department of Physics and Astronomy, The University of Tennessee, University of Tennessee, Physics, University of Tennessee, The University of Tennessee, Department of Phys., Univ. of Tennessee, U. Tennessee, Knoxville, University of Tennessee, Knoxville