2017/10/24 by Y. Nunez-Fernandez, G. Kotliar, K. Hallberg · 1 citation
Physics and Astronomy · #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.97.121113
published as Phys. Rev. B 97, 121113 (2018)
arxiv created 2017/10/24 · arxiv updated 2018/04/04
A repulsive Coulomb interaction between electrons in different orbitals in correlated materials can give rise to bound quasiparticle states. We study the non-hybridized two-orbital Hubbard model with intra (inter)-orbital interaction U (U12) and different band widths using an improved dynamical mean field theory numerical technique which leads to reliable spectra on the real energy axis directly at zero temperature. We find that a finite density of states at the Fermi energy in one band is correlated with the emergence of well defined quasiparticle states at excited energies Δ=U-U12 in the other band. These excitations are inter-band holon-doublon bound states. At the symmetric point U=U12, the quasiparticle peaks are located at the Fermi energy, leading to a simultaneous and continuous Mott transition settling a long-standing controversy.