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Hubbard physics in the PAW GW approximation

Version 2 2024-06-04, 13:11
Version 1 2018-07-10, 10:32
journal contribution
posted on 2024-06-04, 13:11 authored by JM Booth, Daniel Drumm, PS Casey, JS Smith, SP Russo
It is demonstrated that the signatures of the Hubbard Model in the strongly interacting regime can be simulated by modifying the screening in the limit of zero wavevector in Projector-Augmented Wave GW calculations for systems without significant nesting. This modification, when applied to the Mott insulator CuO, results in the opening of the Mott gap by the splitting of states at the Fermi level into upper and lower Hubbard bands, and exhibits a giant transfer of spectral weight upon electron doping. The method is also employed to clearly illustrate that the M1 and M2 forms of vanadium dioxide are fundamentally different types of insulator. Standard GW calculations are sufficient to open a gap in M1 VO2, which arise from the Peierls pairing filling the valence band, creating homopolar bonds. The valence band wavefunctions are stabilized with respect to the conduction band, reducing polarizability and pushing the conduction band eigenvalues to higher energy. The M2 structure, however, opens a gap from strong on-site interactions; it is a Mott insulator.

History

Journal

Journal of Chemical Physics

Volume

144

Article number

ARTN 244110

Location

United States

ISSN

0021-9606

eISSN

1089-7690

Language

English

Publication classification

C1 Refereed article in a scholarly journal

Copyright notice

2016, AIP Publishing

Issue

24

Publisher

AIP Publishing