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arXiv · 1705.04017

Spin Dynamics and Magnetoelectric Coupling Mechanism of Co4Nb2O9

Guochu Deng·Yiming Cao·Wei Ren·Shixun Cao·Andrew J. Studer·Nicolas Gauthier·Michel Kenzelmann·Gene Davidson·Kirrily C. Rule·Jason S. Gardner·Paolo Imperia·Clemens Ulrich·Garry J. McIntyre
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Abstract

Neutron powder diffraction experiments reveal that Co4Nb2O9 forms a noncollinear in-plane magnetic structure with Co2+ moments lying in the ab plane. The spin-wave excitations of this magnet were measured by using inelastic neutron scattering and soundly simulated by a dynamic model involving nearest and next-nearest neighbour exchange interactions, in-plane anisotropy and the Dzyaloshinskii-Moriya interaction. The in-plane magnetic structure of Co4Nb2O9 is attributed to the large in-plane anisotropy while the noncollinearity of the spin configuration is attributed to the Dzyaloshinskii-Moriya interaction. The high magnetoelectric coupling effect of Co4Nb2O9 in fields can be explained by its special in-plane magnetic structure.

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Guochu Deng, Yiming Cao, Wei Ren, Shixun Cao, Andrew J. Studer, Nicolas Gauthier, Michel Kenzelmann, Gene Davidson, Kirrily C. Rule, Jason S. Gardner, Paolo Imperia, Clemens Ulrich, Garry J. McIntyre. 2018-02-27. Spin Dynamics and Magnetoelectric Coupling Mechanism of Co4Nb2O9. https://doi.org/10.1103/physrevb.97.085154

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