Current biasing a multilayered device as a boundary condition for inhomogeneous nonequilibrium dynamical mean-field theory

Recently, nonequilibrium dynamical mean-field theory was developed as a new technique to solve the bulk nonequilibrium many-body problem. The computational effort needed to solve the nonequilibrium problem in the bulk is similar to the efforts needed to solve the inhomogeneous multilayered problem for current flow perpendicular to the planes. Because the leads provide the appropriate boundary conditions for the open system, one can directly solve for the steady state within a frequency representation, and thereby obtain the current-voltage relation for the device. Here we discuss the problem of determining the boundary condition for the Green’s functions, which can be used to determine the so-called self-energy of the leads, which is a critical step needed in this problem.