Flatband in a three-dimensional tungsten nitride compound

X B Ye; P Tuo; B C Pan

doi:10.1063/5.0008739

Flatband in a three-dimensional tungsten nitride compound

J Chem Phys. 2020 Jun 14;152(22):224503. doi: 10.1063/5.0008739.

Authors

X B Ye¹, P Tuo², B C Pan¹

Affiliations

¹ Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
² Key Laboratory of Strongly-Coupled Quantum Matter Physics, Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.

PMID: 32534531
DOI: 10.1063/5.0008739

Abstract

Herein, the flatband of a W₁N₂ crystal is theoretically investigated. It is revealed that the flatband can be well-described by a tight-binding model of the N₁₂ skeleton, where the dispersion of the flatband is governed by both the ppσ bonding strength (V_ppσ) and the ppπ bonding strength (V_ppπ) between the nearest-neighbor N atoms. It is also found that the proper strength of the ppπ bonding between neighboring N atoms plays a prime role in the formation of the flatband. In addition, when the compound is doped with holes, the electrons at the flatband are fully polarized, showing a ferromagnetic character. This behavior has a weak correlation with the on-site Coulomb interaction U. Moreover, several three-dimensional compounds possessing flatbands in the whole k space are predicted.