Comprehensive inelastic neutron scattering study of the multiferroic [Formula: see text]

Jinchen Wang; R S Fishman; Yiming Qiu; J A Fernandez-Baca; Georg Ehlers; K-C Liang; Yaqi Wang; Bernd Lorenz; C W Chu; Feng Ye

doi:10.1103/PhysRevB.98.214425

Comprehensive inelastic neutron scattering study of the multiferroic ${M n}_{1 - x} {C o}_{x} {W O}_{4}$

Phys Rev B. 2018 Dec;98(21):10.1103/PhysRevB.98.214425. doi: 10.1103/PhysRevB.98.214425.

Authors

Jinchen Wang^{1

2}, R S Fishman³, Yiming Qiu⁴, J A Fernandez-Baca², Georg Ehlers⁵, K-C Liang⁶, Yaqi Wang⁶, Bernd Lorenz⁶, C W Chu^{6

7}, Feng Ye²

Affiliations

¹ Department of Physics, Renmin University of China, Beijing 100872, China.
² Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
³ Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
⁴ NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
⁵ Neutron Technologies Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
⁶ Department of Physics and TCSUH, University of Houston, Houston, Texas 77204, USA.
⁷ Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA.

Abstract

Using high-resolution inelastic neutron scattering, we examine the spin dynamics of ${M n}_{1 - x} {C o}_{x} {W O}_{4}$ in the collinear AF1, the $a c - b$ spiral AF2, and the $a c$ cycloidal AF5 phases. The spin wave excitations are well described by a Heisenberg model with competing long-range exchange interactions ( $J_{i}$ up to 12th nearest neighbors) and the single-ion anisotropy $K$ induced by the spin-orbit interaction. While the exchange constants are relatively unchanged, the dominant effect of doping is to change the single-ion anisotropy from easy axis $(K > 0)$ in the collinear AF1 phase to easy plane $(K < 0)$ in the two multiferroic phases.

Grants and funding

9999-NIST/ImNIST/Intramural NIST DOC/United States