Electronic structure of the Falicov-Kimball model with a magnetic field: Dynamical mean-field study

Abstract

The two-dimensional Falicov-Kimball model in the presence of a perpendicular magnetic field is investigated by the dynamical mean-field theory. Within the model the interplay between electron correlations and the fine electron structure due to the magnetic field is essentially emerged. Without electron correlations the magnetic field induces the electron structure to the so-called Hofstadter butterfly. It is found that when electron correlations drives the metal-insulator transition, they simultaneously smear out the fine structure of the Hofstadter butterfly. In a long-range ordered phase, the electron correlation induced gap preserves the fine structure, but it separates the Hofstadter butterfly into two wings.