Quantum Critical Probing and Simulation of Colored Quantum Noise

TL;DR

This paper introduces a protocol for simulating non-Markovian quantum systems by mapping environment correlations into noise, enabling the probing of environment properties and critical phenomena through open system dynamics.

Contribution

It presents a novel method to simulate and analyze non-Markovian quantum noise and environment correlations using a collisional model and matrix-product-states.

Findings

Successful simulation of system dynamics with matrix-product-states

Agreement between full system simulation and variational master equation

Ability to determine environment correlation length and critical properties

Abstract

We propose a protocol to simulate the evolution of a non-Markovian open quantum system by considering a collisional process with a many-body system, which plays the role of an environment. As a result of our protocol the environment spatial correlations are mapped into the time correlations of a noise that drives the dynamics of the open system. Considering the weak coupling limit the open system can also be considered as a probe of the environment properties. In this regard, when preparing the environment in its ground state, a measurement of the dynamics of the open system allows to determine the length of the environment spatial correlations and therefore its critical properties. To illustrate our proposal we simulate the full system dynamics with matrix-product-states and compare this with the reduced dynamics obtained with an approximated variational master equation.