Fig. 2: Formation of split-off flat bands in nonmagnetic monoclinic VO2.
From: Hidden magnetism and split off flat bands in the insulator metal transition in VO2
a, b Electronic structures of nonmagnetic VO2 from the revised Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional (R-PBE)51. DBA = 0% corresponds to the symmetry unbroken rutile structure in the M-like unit cell subject to structural minimization with R-PBE. ∆Eint in a indicates the internal gap between the principal conduction band and the principal valence band. DBA = 25.6% in b was obtained via structural minimization of the M phase with R-PBE. Bold red curves indicate the bands that are split off from the principal conduction band as the DBA increases. The yellow highlight in b indicates the gap between the lowest conduction band and the highest, split-off valence band. c Partial charge density of the split-off bands shown by bold red curves in b (isosurface: 0.01 \(\left|{\rm{e}}\right|{{\rm{bohr}}}^{-3}\)).
