Ferroelectricity in a Collinear Magnetic Phase of Orthorhombic Perovskites

ORAL

Abstract

Below $T_c$ = 30 K, a number of perovskite manganites (such as HoMnO$_3$) and nickelates order magnetically in the so-called E-type phase with zigzag chains of parallel spins. We demonstrate that this magnetic phase is also ferroelectric. We discuss the magnetoelectric coupling based on the symmetry arguments of the Landau theory of phase transitions. We also explore a microscopic mechanism of ferroelectricity induced by the collinear spin arrangement and address the order of magnitude of the ferroelectric polarization.

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Authors

  • Ivan Sergienko

    • Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee
    • Oak Ridge National Laboratory

  • Cengiz Sen

    • National High Magnetic Field Lab and Florida State University, Tallahassee, FL
    • National High Magnetic Field Laboratory

  • Elbio Dagotto

    • Oak Ridge National Lab, Oak Ridge, TN and University of Tennessee, Knoxville, TN
    • The University of Tennessee at Knoxville and ORNL
    • Oak Ridge National Laboratory, Materials Science and Technology Division and University of Tennessee, Knoxville
    • University of Tennessee and Oak Ridge National Laboratory