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DOE OSTI · 1798803

A room temperature polar magnetic metal

Abstract

The emergence of long-range magnetic order in noncentrosymmetric compounds has stimulated interest in the possibility of exotic spin transport phenomena and topologically protected spin textures for applications in next-generation spintronics. Polar magnets, with broken symmetries of spatial inversion and time reversal, usually host chiral spin textures. This work reports on a wurtzite-structure polar magnetic metal, identified as AA'-stacked (Fe 0.5 Co 0.5 ) 5 GeTe 2 , which exhibits a Néel-type skyrmion lattice as well as a Rashba-Edelstein effect at room temperature. Atomic resolution imaging of the structure reveals a structural transition as a function of Co-substitution, leading to the emergence of the polar phase at 50% Co. We report this discovery reveals an unprecedented layered polar magnetic system for investigating intriguing spin topologies, and it ushers in a promising new framework for spintronics.

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BibTeXRIS

Zhang, Hongrui, Shao, Yu-Tsun, Chen, Rui, Chen, Xiang, Susarla, Sandhya, Raftrey, David, Reichanadter, Jonathan T., Caretta, Lucas, Huang, Xiaoxi, Settineri, Nicholas S., Chen, Zhen, Zhou, Jingcheng, Bourret-Courchesne, Edith, Ercius, Peter, Yao, Jie, Fischer, Peter, Neaton, Jeffrey B., Muller, David A., Birgeneau, Robert J., Ramesh, Ramamoorthy. 2022-04-06. A room temperature polar magnetic metal. https://doi.org/10.1103/physrevmaterials.6.044403

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36 MATERIALS SCIENCE↗