  We study the occurrence of negative differential conductance induced by
resonance effects in a model for a multilayer heterostructure. In particular,
we consider a system consisting of several correlated and non-correlated
monoatomic layers, sandwiched between two metallic leads. The geometry confines
electrons in wells within the heterostructures, which are connected to each
other and to the leads by tunneling processes. The non-equilibrium situation is
produced by applying a bias-voltage to the leads. Our results show that for
specific values of the parameters resonance tunneling takes place. We
investigate in detail its influence on the current-voltage characteristics. Our
results are obtained via non-equilibrium real-space dynamical mean-field
theory. As an impurity solver we use the so-called auxiliary master equation
approach, which addresses the impurity problem within an auxiliary system
consisting of a correlated impurity, a small number of uncorrelated bath sites,
and two Markovian environments described by a generalized master equation.
