Doping-driven metal-insulator transition in correlated electron systems with strong Hund's exchange coupling

We study the doping-driven Mott metal-insulator transition for multiorbital Hubbard models with Hund's exchange coupling at finite temperatures. As in the single-orbital Hubbard model, the transition is first order within dynamical mean-field theory, with a coexistence region where two solutions can be stabilized. We find that in the presence of finite Hund's coupling, the insulating phase is connected to a badly metallic phase, which extends to surprisingly large dopings. While fractional power-law behavior of the self-energies on the Matsubara axis is found on both sides of the transition, a regime with frozen local moments develops only on the branch connected to the insulating phase.