Master equation based steady-state cluster perturbation theory

Article

关键词: SINGLE-MOLECULE JUNCTIONS;    MEAN-FIELD THEORY;    QUANTUM TRANSPORT;    RENORMALIZATION-GROUP;    ELECTRON-TRANSPORT;    CONDUCTANCE;    DEPENDENCE;    SYSTEMS;    ENERGY;   

DOI  :  10.1103/PhysRevB.92.125128

来源: SCIE

【 摘 要 】

A simple and efficient approximation scheme to study electronic transport characteristics of strongly correlated nanodevices, molecular junctions, or heterostructures out of equilibrium is provided by steady-state cluster perturbation theory. In this work, we improve the starting point of this perturbative, nonequilibrium Green's function based method. Specifically, we employ an improved unperturbed (so-called reference) state. (rho) over cap (S), constructed as the steady state of a quantum master equation within the Born-Markov approximation. This resulting hybrid method inherits beneficial aspects of both the quantum master equation as well as the nonequilibrium Green's function technique. We benchmark this scheme on two experimentally relevant systems in the single-electron transistor regime: an electron-electron interaction based quantum diode and a triple quantum dot ring junction, which both feature negative differential conductance. The results of this method improve significantly with respect to the plain quantum master equation treatment at modest additional computational cost.

【 授权许可】

Free