Temperature-dependent quasiparticle band structure of the ferromagnetic semiconductor EuS

We present calculations for the temperature-dependent electronic structure of the ferromagnetic semiconductor EuS. A combination of a many-body evaluation of a multiband Kondo-lattice model and a first-principles $T=0$\char21{}band-structure calculation [tight-binding linear muffin-tin orbital (TB-LMTO)] is used to get realistic information about temperature- and correlation effects in the EuS energy spectrum. The combined method strictly avoids double-counting of any relevant interaction. Results for EuS are presented in terms of spectral densities, quasiparticle band structures, and quasiparticle densities of states, and that over the entire temperature range.