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arXiv · 2008.05702

Atomic structures and electronic correlation of monolayer 1T-TaSe2

Jae Whan Park·Han Woong Yeom
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Abstract

We investigate atomic and electronic structures of monolayer 1T-TaSe2 using density functional theory calculations. Monolayers of 1T-TaSe2 were recently grown on graphene substrates and suggested as an intriguing Mott insulator [Nat. Phys. 16, 218 (2020)]. However, the prevailing structural model for the model system of 1T-TaS2, the cation-centered cluster of a David-star shape with strong electron correlation, could not explain the characteristic and unusual orbital splitting observed in scanning tunneling spectroscopy experiments. We suggest an alternative structure model, an anion-centered cluster structure, which can reproduce most of the unusual spectroscopic characteristics with electron doping from the substrate without electron correlation. The unusual spectroscopic features observed, thus, seems to indicate a simple and usual band insulating state. This work indicates the importance of a large structural degree of freedom given for a cluster Mott insulator.

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Jae Whan Park, Han Woong Yeom. 2020-08-13. Atomic structures and electronic correlation of monolayer 1T-TaSe2. https://arxiv.org/abs/2008.05702

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