Nonequilibrium Dynamical Mean Field Theory: an auxiliary Quantum Master Equation approach

We introduce a versatile method to compute electronic steady state properties of strongly correlated extended quantum systems out of equilibrium. The approach is based on dynamical mean-field theory (DMFT), in which the original system is mapped onto an auxiliary non-equilibrium impurity problem imbedded in a Markovian environment. The steady state Green's function of the auxiliary system is solved by full diagonalization of the corresponding Lindblad equation. The approach can be regarded as the nontrivial extension of the exact-diagonalization based DMFT to the non-equilibrium case. As a first application, we consider an interacting Hubbard layer attached to two metallic leads and present results for the steady-state current and the non-equilibrium density of states.