Diagrammatic Monte Carlo simulation of non-equilibrium systems

TL;DR

This paper extends diagrammatic Monte Carlo methods to real-time nonequilibrium quantum systems, enabling detailed study of transport and relaxation in quantum dots using both weak and strong coupling approaches.

Contribution

It introduces a generalized Keldysh formalism for diagrammatic Monte Carlo, applicable to non-equilibrium quantum impurity models, combining weak and strong coupling techniques.

Findings

Successfully applied to quantum dot transport simulations

Analyzed relaxation dynamics in interacting systems

Demonstrated versatility of the method in non-equilibrium settings

Abstract

We generalize the recently developed diagrammatic Monte Carlo techniques for quantum impurity models from an imaginary time to a Keldysh formalism suitable for real-time and nonequilibrium calculations. Both weak-coupling and strong-coupling based methods are introduced, analysed and applied to the study of transport and relaxation dynamics in interacting quantum dots.