相关论文: Implementation of a non-equilibrium Green's functi…
Nonequilibrium quantum mechanics can be solved with the Keldysh formalism, which evolves the quantum mechanical states forward in time in the presence of a time-dependent field, and then evolves them backward in time, undoing the effect of…
Non equilibrium Green's function methods are regularly used to calculate current and charge densities in nanoscale (both molecular and semiconductor) conductors under bias. This method is mainly used for ballistic conduction but may be…
We review a unified approach for computing: (i) spin-transfer torque in magnetic trilayers like spin-valves and magnetic tunnel junction, where injected charge current flows perpendicularly to interfaces; and (ii) spin-orbit torque in…
Dynamical magnets can pump spin currents into superconductors. To understand such a phenomenon, we develop a method utilizing the generalized Usadel equation to describe time-dependent situations in superconductors in contact with dynamical…
We study the nonlinear elastic quantum electronic transport properties of nanoscopic devices using the Nonequilibrium Green's function (NEGF) method. The Green's function method allows us to expand the $I-V$ characteristics of a given…
Using non-equilibrium Green's functions combined with many-body perturbation theory, we have calculated steady-state densities and currents through short interacting chains subject to a finite electric bias. By using a steady-state…
A free electron description of spin-dependent tranport in magnetic tunnel junctions with non collinear magnetizations is presented. We investigate the origin of transverse spin density in tunnelling transport and the quantum interferences…
We present a scattering approach for the study of the transport and thermodynamics of quantum systems strongly coupled to their thermal environment(s). This formalism recovers the standard non-equilibrium Green's function expressions for…
Using Density functional theory and non-equilibrium Green's function formalism, spin dependent electron transport in Fe/Mo$_x$Cr$_{1-x}$S$_2$/Fe magnetic tunnel junction is studied. Spin transport for different thicknesses (1, 3, 5, and 7…
Two-terminal spintronic devices remain challenging to model under realistic operating conditions, where the interplay of complex electronic structures, correlation effects and bias-driven non-equilibrium dynamics may significantly impact…
This paper is devoted to the study and interpretation of the spectral function $\mathbf{A}(\omega, T)$ of the Keldysh nonequilibrium Green's function. The spatial diagonal of the spectral function is often interpreted as a time-dependent…
By incorporating the proper boundary conditions, we analytically derive the impulse response (or "Green's function") of a current-sensing spin detector. We also compare this result to a Monte-Carlo simulation (which automatically takes the…
Electronic properties of heterostructures in which a finite number of Mott-insulator layers are sandwiched by semi-infinite metallic leads are investigated by using the dynamical-mean-field method combined with the Keldysh Green's function…
An efficient implementation of the nonequilibrium Green function (NEGF) method combined with the density functional theory (DFT) using localized pseudo-atomic orbitals (PAOs) is presented for electronic transport calculations of a system…
The increasing interest in nonequilibrium effects in condensed matter theory motivates the adaption of diverse equilibrium techniques to Keldysh formalism. For methods based on multi-particle Green or vertex functions this involves a…
We describe an ab initio method for calculating the electronic structure, electronic transport, and forces acting on the atoms, for atomic scale systems connected to semi-infinite electrodes and with an applied voltage bias. Our method is…
Understanding non-equilibrium spin transport through 2D ferromagnets is a theoretical challenge, as correlations produce a complex electronic structure with coexisting itinerant and localized electrons. We have developed a fully…
It is shown how to construct Keldysh diagram technique for pseudo - particle approach to the Hubbard model. We propose self consistent equations for pseudo particle and electron Green functions in Keldysh diagram technique. Nonlocal effects…
We investigate coherent transport through open lateral quantum dots using recursive Green's function technique, incorporating exchange-correlation effects within local spin-density approximation (LSDA). At low electron densities the current…
We formulate the many-body spin dynamics at high temperature within the non-equilibrium Keldysh formalism. For the simplest XY interaction, analytical expressions in terms of the one particle solutions are obtained for linear and ring…