Quantum correlations and entanglement in a model comprised of a short chain of nonlinear oscillators

TL;DR

This paper models a chain of three nonlinear oscillators as a three-qubit system, demonstrating the generation and persistence of tripartite entanglement under damping, and analyzing correlations within the system.

Contribution

It introduces a novel approach to treat a chain of nonlinear oscillators as a three-qubit model, enabling analysis of entanglement dynamics and correlations.

Findings

Tripartite entanglement can be generated in the system.

Some entanglement persists over long times despite damping.

Relations between correlations and entanglement are established.

Abstract

We discuss a model comprised of a chain of three Kerr-like nonlinear oscillators pumped by two modes of external coherent field. We show that the system can be treated as nonlinear quantum scissors and behave as a three-qubit model. For such situation, different types of tripartite entangled states can be generated, even when damping effects are present in the system. Some amount of such entanglement can survive even in a long-time limit. The flow of bipartite entanglement between subsystems of the model and relations among first-order correlations, second-order correlations, and the entanglement are discussed.