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arXiv · 1907.06185

Evidence for metallic 1T phase, 3d1 electronic configuration and charge density wave order in molecular-beam epitaxy grown monolayer VTe2

Ping Kwan Johnny Wong·Wen Zhang·Jun Zhou·Fabio Bussolotti·Xinmao Yin·Lei Zhang·Alpha T. NDiaye·Simon A Morton·Wei Chen·Kuan Eng Johnson Goh·Michel P de Jong·Yuan Ping Feng·Andrew Thye Shen Wee
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Abstract

We present a combined experimental and theoretical study of monolayer VTe2 grown on highly oriented pyrolytic graphite by molecular-beam epitaxy. Using various in-situ microscopic and spectroscopic techniques, including scanning tunneling microscopy/spectroscopy, synchrotron X-ray and angle-resolved photoemission, and X-ray absorption, together with theoretical analysis by density functional theory calculations, we demonstrate direct evidence of the metallic 1T phase and 3d1 electronic configuration in monolayer VTe2 that also features a (4 x 4) charge density wave order at low temperatures. In contrast to previous theoretical predictions, our element-specific characterization by X-ray magnetic circular dichroism rules out a ferromagnetic order intrinsic to the monolayer. Our findings provide essential knowledge necessary for understanding this interesting yet less explored metallic monolayer in the emerging family of van der Waals magnets.

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Ping Kwan Johnny Wong, Wen Zhang, Jun Zhou, Fabio Bussolotti, Xinmao Yin, Lei Zhang, Alpha T. NDiaye, Simon A Morton, Wei Chen, Kuan Eng Johnson Goh, Michel P de Jong, Yuan Ping Feng, Andrew Thye Shen Wee. 2019-07-14. Evidence for metallic 1T phase, 3d1 electronic configuration and charge density wave order in molecular-beam epitaxy grown monolayer VTe2. https://doi.org/10.1021/acsnano.9b05349

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