Resonance effects in correlated multilayer heterostructures

Abstract

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.

Nonequilibrium Kondo effect in a magnetic field: auxiliary master equation approach

“…In summary, it is convenient to use AMEA, whenever very long time scales are needed, or when information over the full energy range is required, as it is the case in the determination of spectral functions. For example, AMEA is an interesting tool for DMFT in nonequilibrium, where spectral functions are needed explicitly [26,[55][56][57][58][59]. On the other hand, the NRG-tDMRG approach is more flexible with respect to the parameter regime, as it uses an explicit renormalization of the impurity.…”

Simulation methods for open quantum many-body systems

“…DMFT is a mapping of a many-body lattice model onto a single impurity problem that has to be solved in a self-consistent way (Georges et al, 1996). Initially, effective Lindblad master equations have been used to describe quantum transport in closed quantum systems using DMFT (Arrigoni et al, 2013;Titvinidze et al, 2015Titvinidze et al, , 2016. Recently, this approach has been extended to the case where already the initial many-body problem describes an open quantum system (Panas et al, 2019).…”

Density-wave steady-state phase of dissipative ultracold fermions with nearest-neighbor interactions

“…Recent proposals include engineering dissipative dynamics to create entangled states [8] or to drive the system to Bose-Einstein condensation [9]. The study of open quantum systems is also useful for investigating transport properties of quantum dots [10][11][12][13] or correlated structures [14][15][16][17].…”

“…To investigate this problem we employ the recently developed Lindblad dynamical mean-field theory (L-DMFT) [15][16][17]. Although DMFT has some limitations due to its local self-energy -without non-local extensions it cannot describe, e.g., d -wave superconductivity [57] -it has proven highly successful in the study of correlated lattice problems [58].…”