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arXiv · 2103.01360

Field-tunable toroidal moment in a chiral-lattice magnet

Lei Ding·Xianghan Xu·Harald O. Jeschke·Xiaojian Bai·Erxi Feng·Admasu Solomon Alemayehu·Jaewook Kim·Feiting Huang·Qiang Zhang·Xiaxin Ding·Neil Harrison·Vivien Zapf·Daniel Khomskii·Igor I. Mazin·Sang-Wook Cheong·Huibo Cao
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Abstract

A toroidal dipole moment appears independent of the electric and magnetic dipole moment in the multipole expansion of electrodynamics. It arises naturally from vortex-like arrangements of spins. Observing and controlling spontaneous long-range orders of toroidal moments are highly promising for spintronics but remain challenging. Here we demonstrate that a vortex-like spin configuration with a staggered arrangement of toroidal moments, a ferritoroidal state, is realized in a chiral triangular-lattice magnet BaCoSiO4. Upon applying a magnetic field, we observe multi-stair toroidal transitions correlating directly with metamagnetic transitions. We establish a first-principles microscopic Hamiltonian that explains both the formation of toroidal states and the metamagnetic toroidal transition as a combined effect of the magnetic frustration and the Dzyaloshinskii-Moriya interactions allowed by the crystallographic chirality in BaCoSiO4.

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Lei Ding, Xianghan Xu, Harald O. Jeschke, Xiaojian Bai, Erxi Feng, Admasu Solomon Alemayehu, Jaewook Kim, Feiting Huang, Qiang Zhang, Xiaxin Ding, Neil Harrison, Vivien Zapf, Daniel Khomskii, Igor I. Mazin, Sang-Wook Cheong, Huibo Cao. 2021-03-01. Field-tunable toroidal moment in a chiral-lattice magnet. https://doi.org/10.1038/s41467-021-25657-6

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