Spectral functions of the Falicov-Kimball model with electronic ferroelectricity

We calculate the angular resolved photoemission spectrum of the Falicov-Kimball model with electronic ferroelectricity where d-and f-electrons have different hoppings. In mix-valence regimes, the presence of strong scattering processes between d–f excitons and a hole, created by emission of an electron, leads to the formation of pseudospin polarons and novel electronic structures with bandwidth scaling with that of d–f excitons. Especially, in the two-dimensional case, we find that flat regions exist near the bottom of the quasiparticle band in a wide range of the d-and f-level energy difference.