Hidden Local Symmetry Breaking for Understanding the Peculiar Magnetism in Co3Sn2S2
Scientific Achievement
It is seen that the onset of ferromagnetic order in the Kagome-lattice magnetic Weyl semi-metal Co3Sn2S2 is accompanied by a broken local symmetry describable as a rhombohedral to monoclinic distortion.
Significance and Impact
Co3Sn2S2 exhibits global rhombohedral symmetry, but local distortions lead to the formation of a low temperature spin glass state despite the absence of lattice or site disorder; similar local symmetry breaking could be the key to understanding unusual magnetic and electronic ground states of other topological materials.
Research Details
- Average ferromagnetic order and moment were identified with half-polarized neutron diffraction measurements.
- Average and local crystal structures were determined by both conventional powder neutron diffraction and total scattering measurements.
- Density functional theory calculations unveils the effect of the local symmetry breaking on the local ferromagnetic instability and Weyl physics.
“Hidden Local Symmetry Breaking in a Kagome-Lattice Magnetic Weyl Semimetal”
Qiang Zhang, Yuanpeng Zhang, Masaaki Matsuda, Vasile Garlea, Jiaqiang Yan, Michael McGuire, D. Alan Tennant, and Satoshi Okamoto
Journal of the American Chemical Society 144, 14339−14350 (2022). DOI: https://doi.org/10.1021/jacs.2c05665
