Influence of classic noise on entangled state formation in parametric systems

TL;DR

This paper investigates how classical noise affects the formation and lifetime of entangled states in a system of two coupled quantum oscillators with a partially coherent pump, using a quantum stochastic approach.

Contribution

It introduces a model considering partial coherence of the pump and analyzes its impact on entanglement dynamics in open quantum systems.

Findings

Partial coherence shortens entangled state lifetime

Threshold conditions for entanglement formation are identified

Numerical results show entanglement dynamics depend on pump coherence

Abstract

A study of "high temperature" entangled states in a system of two parametrically coupled quantum oscillators placed into independent thermal baths is performed taking into account partially coherent parametric pump. Processes in an open system are considered based on the Heisenberg-Langevin formalism. We obtain a closed system of equations for the averaged quadratic correlation functions in quantum stochastic problem as a result of Markov processes approximation. On the basis of numerical calculations the dynamics of the logarithmic negativity, which is the measure of entanglement in the system, is investigated. It is shown that the partial coherence of the parametric pump makes the lifetime of the entangled states finite. The threshold characteristics of the formation and existence of these states are specified.