Nonlocal correlations and spectral properties of the Falicov-Kimball model

作者:Ribic T*; Rohringer G; Held K
来源:Physical Review B, 2016, 93(19): 195105.
DOI:10.1103/PhysRevB.93.195105

摘要

We derive an analytical expression for the local two-particle vertex of the Falicov-Kimball model, including its dependence on all three frequencies, the full vertex, and all reducible vertices. This allows us to calculate the self-energy in diagrammatic extensions of dynamical mean field theory, specifically in the dual fermion and the one-particle irreducible approach. Nonlocal correlations are thence included and originate here from charge-density wave fluctuations. At low temperatures and in two dimensions, they lead to a larger self-energy contribution at low frequencies and a more insulating spectrum.

  • 出版日期2016-5-2