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arXiv · 2104.00346

Identification of the Mott insulating CDW state in 1T-TaS$_2$

Dongbin Shin·Nicolas Tancogne-Dejean·Jin Zhang·Mahmut Sait Okyay·Angel Rubio·Noejung Park
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Abstract

We investigate the low-temperature charge-density-wave (CDW) state of bulk TaS$_2$ with a fully self-consistent DFT+U approach, over which the controversy has remained unresolved regarding the out-of-plane metallic band. By examining the innate structure of the Hubbard U potential, we reveal that the conventional use of atomic-orbital basis could seriously misevaluate the electron correlation in the CDW state. By adopting a generalized basis, covering the whole David star, we successfully reproduce the Mott insulating nature with the layer-by-layer antiferromagnetic order. Similar consideration should be applied for description of the electron correlation in molecular solid.

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Dongbin Shin, Nicolas Tancogne-Dejean, Jin Zhang, Mahmut Sait Okyay, Angel Rubio, Noejung Park. 2021-04-01. Identification of the Mott insulating CDW state in 1T-TaS$_2$. https://doi.org/10.1103/physrevlett.126.196406

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