Origin of strong dispersion in Hubbard insulators

Academic Article

Abstract

  • © 2015 American Physical Society. Using cluster perturbation theory, we explain the origin of the strongly dispersive feature found at high binding energy in the spectral function of the Hubbard model. By comparing the Hubbard and t-J-3s model spectra, we show that this dispersion does not originate from either coupling to spin fluctuations (∼J) or the free hopping (∼t). Instead, it should be attributed to a long-range, correlated hopping ∼t2/U, which allows an effectively free motion of the hole within the same antiferromagnetic sublattice. This origin explains both the formation of the high-energy anomaly in the single-particle spectrum and the sensitivity of the high-binding-energy dispersion to the next-nearest-neighbor hopping t′.
  • Digital Object Identifier (doi)

    Author List

  • Wang Y; Wohlfeld K; Moritz B; Jia CJ; Van Veenendaal M; Wu K; Chen CC; Devereaux TP
  • Volume

  • 92
  • Issue

  • 7