Far-infrared transmission spectroscopy studies of HoMn$_{2}$O$_{5}$ single crystals at the commensurate-incommensurate phase transition

ORAL

Abstract

Spectra of the low-frequency IR-active excitations in HoMn$_{2}$O$_{5}$ multiferroic single crystals have been studied using synchrotron radiation based far-infrared transmission spectroscopy at U12IR beamline of NSLS-BNL in the frequency range between 8.5 and 105 cm$^{-1}$. Both preferable polarization of IR-active excitations along crystallographic directions of HoMn$_{2}$O$_{5}$ and temperature variation of their oscillator strength reveal strong changes at the commensurate-incommensurate phase transition at $T_{3 }$= 19 K. Transmission spectra are interpreted in terms of the electromagnon, magnon, and crystal-field splitting excitations.

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Authors

  • A.A. Sirenko

    Department of Physics, New Jersey Institute of Technology, Newark, NJ 07102

  • S. Park

    Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, Department of Physics, Rutgers University, Rutgers University

  • S. M. O' Malley

    Department of Physics, New Jersey Institute of Technology, Newark, NJ 07102

  • G. L. Carr

    Brookhaven National Laboratory, NSLS, Brookhaven National Laboratory, Upton, New York 11973

  • SangWook Cheong

    Department of Physics \& Astronomy, Rutgers University, Piscataway, New Jersey 08854, Physics Department, Rutgers University, Rutgers University, Dept. of Physics and Astronomy, Rutgers University, Rutgers Center for Emergent Materials, Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, Department of Physics, Rutgers, Rutgers Univ.