Non-equilibrium inhomogeneous DMFT for correlated heterostuctures

Here we present our results for the system consisting of several correlated and non-correlated
monoatomic layers, sandwiched between two metallic leads. The non-equilibrium situation is
driven by applying a bias-voltage to the leads. We obtain that current, as a function of the bias
voltage, has two maximums. One of them is due to the finite bandwidth of the leads, while other
is due to the resonance effects. Here we concentrate on the latter maximum and investigate its
origin in detail.
We also present our new results about Seebeck effect for a single correlated metallic layer sand-
wiched between two metallic leads. The non-equilibrium situation is driven by applying a bias-
voltage and temperature gradient between leads. Due to the temperature difference current flows
opposite to the potential difference and so we extract energy due to the temperature difference.
We calculate the voltage for which the extracted power is maximal.
For this purpose we use recently introduced dynamical mean-field theory (DMFT) based theoret-
ical scheme [1], which addresses the DMFT impurity problem within an auxiliary system con-
sisting of a correlated impurity, a small number of uncorrelated bath sites and two Markovian en-
vironments described by a generalized Master equation [1,2,3]. For the multilayer case one needs
to generalize it and take into account the spatial inhomogeneity of the layers [4].
References:
[1] E. Arrigoni et al., Phys, Rev. Lett. 110, 086403 (2013)
[2] A. Dorda et al., Phys. Rev. B 89, 165105 (2014)
[3] I. Titvinidze et al., Phys. Rev. B 92, 245125 (2015)
[4] M. Potthoff and W. Nolting, Phys. Rev. B 59, 2549 (1999)