1. Evidence of Spin Frustration in a Vanadium Diselenide Monolayer Magnet
- Author
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Wong, P. K. J., Zhang, W., Bussolotti, F., Yin, X., Herng, T. S., Zhang, L., Huang, Y. L., Vinai, G., Krishnamurthi, S., Bukhvalov, D. W., Zheng, Y. J., Chua, R., N'Diaye, A. T., Morton, S. A., Yang, C. -Y., Ou, Yang, K. -H., Torelli, P., Chen, W., Goh, K. E. J., Ding, J., Lin, M. -T., Brocks, G., de, Jong, M. P., Castro, Neto, A. H., Wee, A. T. S., Wong, P. K. J., Zhang, W., Bussolotti, F., Yin, X., Herng, T. S., Zhang, L., Huang, Y. L., Vinai, G., Krishnamurthi, S., Bukhvalov, D. W., Zheng, Y. J., Chua, R., N'Diaye, A. T., Morton, S. A., Yang, C. -Y., Ou, Yang, K. -H., Torelli, P., Chen, W., Goh, K. E. J., Ding, J., Lin, M. -T., Brocks, G., de, Jong, M. P., Castro, Neto, A. H., and Wee, A. T. S.
- Abstract
Monolayer VSe2, featuring both charge density wave and magnetism phenomena, represents a unique van der Waals magnet in the family of metallic 2D transition-metal dichalcogenides (2D-TMDs). Herein, by means of in situ microscopy and spectroscopic techniques, including scanning tunneling microscopy/spectroscopy, synchrotron X-ray and angle-resolved photoemission, and X-ray absorption, direct spectroscopic signatures are established, that identify the metallic 1T-phase and vanadium 3d1 electronic configuration in monolayer VSe2 grown on graphite by molecular-beam epitaxy. Element-specific X-ray magnetic circular dichroism, complemented with magnetic susceptibility measurements, further reveals monolayer VSe2 as a frustrated magnet, with its spins exhibiting subtle correlations, albeit in the absence of a long-range magnetic order down to 2 K and up to a 7 T magnetic field. This observation is attributed to the relative stability of the ferromagnetic and antiferromagnetic ground states, arising from its atomic-scale structural features, such as rotational disorders and edges. The results of this study extend the current understanding of metallic 2D-TMDs in the search for exotic low-dimensional quantum phenomena, and stimulate further theoretical and experimental studies on van der Waals monolayer magnets. © 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
- Published
- 2019