Accelerated calculation of impurity Green's functions exploiting the extreme Mpemba effect

TL;DR

This paper introduces an efficient computational scheme for impurity Green's functions in quantum models by leveraging the non-Markovian quantum Mpemba effect, significantly reducing computational costs in simulating complex quantum dynamics.

Contribution

The authors develop a novel method combining the non-Markovian quantum Mpemba effect with a dynamical map framework to compute two-time impurity correlation functions more efficiently.

Findings

Demonstrates significant computational savings over existing methods.

Accurately benchmarks against exact results in impurity models.

Applicable to both fermionic and bosonic environments.

Abstract

Simulating the dynamics of quantum impurity models remains a fundamental challenge due to the complex memory effects that arise from system-environment interactions. Of particular interest are two-time correlation functions of an impurity, which are central to the characterization of these many-body systems, and are a cornerstone of the description of correlated materials in dynamical mean field theory (DMFT). In this work, we extend our previous work on the extrapolation of single-time observables to demonstrate an efficient scheme for computing two-time impurity correlation functions, by combining the non-Markovian quantum Mpemba effect (NMQMpE) with a dynamical map-based framework for open quantum systems. Our method is benchmarked against exact and known accurate results in prototypical impurity models for both fermionic and bosonic environments, demonstrating significant computational savings compared to state-of-the-art methods.