Non-equilibrium inhomogeneous DMFT for correlated Heterostructures

Due to the experimental progress made in different microscopically control-
ling quantum mechanical systems quantum many body systems out of equilib-
rium have recently attracted increasing interest.
In this talk we present new developments of a recently introduced [1] theo-
retical scheme to deal with correlated system out of equilibrium. This approach
allows to efficiently investigate steady-state behavior of the system based upon
dynamical-mean-field theory (DMFT) within the nonequilibrium (Keldysh) Green’s
functions formalism [2].
The main novelty of the method is in the solution of the impurity prob-
lem. Here the idea is that the baths coupled to the interacting impurity are
replaced by a finite number of bath sites coupled to Markovian reservoirs [1,
3]. Up to now the method has been applied to a single correlated layer sand-
wiched between two metallic leads at different chemical potentials. Here we
show how to extend it to more complex geometries to treat more physically
relevant heterostructures. In articular we present results for the steady-state
current, spectral function and self-energy. First, we will review the case of a
single correlated layer and show the effect of the local Hubbard interaction and
bias voltage for weak and the intermediate hybridization strength to the leads.
Afterwards we present results for systems of particular interest, such as charge
modulated super-lattices, modulated doping close to the Mott insulator, and
resonance effects.
[1] E. Arrigoni et al, Phys. Rev. Lett. 110, 086403 (2013).
[2] J.K. Freericks, V. M. Turkowski, and V. Zlatic, Phys. Rev. Lett. 97, 266408
(2006)
[3] A. Dorda et al, Phys. Rev. B. 89, 165105 (2014).