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arXiv · 1903.01409

Evolution of interlayer and intralayer magnetism in three atomically thin chromium trihalides

Hyun Ho Kim·Bowen Yang·Siwen Li·Shengwei Jiang·Chenhao Jin·Zui Tao·George Nichols·Francois Sfigakis·Shazhou Zhong·Chenghe Li·Shangjie Tian·David G. Cory·Guo-Xing Miao·Jie Shan·Kin Fai Mak·Hechang Lei·Kai Sun·Liuyan Zhao·Adam W. Tsen
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Abstract

We conduct a comprehensive study of three different magnetic semiconductors, CrI$_3$, CrBr$_3$, and CrCl$_3$, by incorporating both few- and bi-layer samples in van der Waals tunnel junctions. We find that the interlayer magnetic ordering, exchange gap, magnetic anisotropy, as well as magnon excitations evolve systematically with changing halogen atom. By fitting to a spin wave theory that accounts for nearest neighbor exchange interactions, we are able to further determine a simple spin Hamiltonian describing all three systems. These results extend the 2D magnetism platform to Ising, Heisenberg, and XY spin classes in a single material family. Using magneto-optical measurements, we additionally demonstrate that ferromagnetism can be stabilized down to monolayer in more isotropic CrBr$_3$, with transition temperature still close to that of the bulk.

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Hyun Ho Kim, Bowen Yang, Siwen Li, Shengwei Jiang, Chenhao Jin, Zui Tao, George Nichols, Francois Sfigakis, Shazhou Zhong, Chenghe Li, Shangjie Tian, David G. Cory, Guo-Xing Miao, Jie Shan, Kin Fai Mak, Hechang Lei, Kai Sun, Liuyan Zhao, Adam W. Tsen. 2019-03-04. Evolution of interlayer and intralayer magnetism in three atomically thin chromium trihalides. https://doi.org/10.1073/pnas.1902100116

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