Evidence of Spin Frustration in a Vanadium Diselenide Monolayer Magnet. Issue 23 (18th April 2019)

• Record Type: Journal Article
• Authors: Wong, Ping Kwan Johnny; Zhang, Wen; Bussolotti, Fabio; Yin, Xinmao; Herng, Tun Seng; Zhang, Lei; Huang, Yu Li; Vinai, Giovanni; Krishnamurthi, Sridevi; Bukhvalov, Danil W.; Zheng, Yu Jie; Chua, Rebekah; N'Diaye, Alpha T.; Morton, Simon A.; Yang, Chao‐Yao; Ou Yang, Kui‐Hon; Torelli, Piero; Chen, Wei; Goh, Kuan Eng Johnson; Ding, Jun; Lin, Minn‐Tsong; Brocks, Geert; de Jong, Michel P.; Castro Neto, Antonio H.; Wee, Andrew Thye Shen
• Is Part Of: Advanced materials. Volume 31:Issue 23(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-04-18
• Subjects: 2D materials -- monolayer magnet -- spin frustration -- van der Waals epitaxy -- vanadium diselenide; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201901185
• Languages: English
• ISSNs: 0935-9648

Abstract

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 3d 1 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. Abstract : Monolayer VSe2 represents a unique system for exploring the interplay between charge density wave and magnetism phenomena. Evidence of spin frustration is obtained in monolayer VSe2, which is significant toward the search for exotic low‐dimensional quantum phases and further theoretical and experimental studies of van der Waals monolayer magnets.