Dissipative preparation of tripartite singlet state in coupled arrays of cavities via quantum feedback control

TL;DR

This paper presents a feasible method to generate a tripartite entangled state in a cavity array using dissipative processes and quantum feedback, achieving high fidelity even with detection inefficiencies.

Contribution

It introduces a novel dissipative scheme combining coherent driving and feedback control for preparing tripartite singlet states in coupled cavity arrays.

Findings

Achieves over 90% fidelity for the target state.

Fidelity is robust against detection inefficiencies.

Effective for high cooperativity parameters above 350.

Abstract

We propose an experimentally feasible scheme for dissipative preparation of tripartite entangled state with atoms separately trapped in an array of three coupled cavities. The combination of coherent driving fields and quantum-jump-based feedback control will drive the system into a non-equilibrium steady state, which has a nearly perfect overlap with the genuine three-atom singlet state. Different control strategies are investigated and the corresponding optimal parameters are confirmed. Moreover, the fidelity of target state is insensitive to detection inefficiencies, and it oversteps 90\% for a wide range of decoherence parameters as long as the single-atom cooperativity parameter $C\equiv g^2/(\gamma\kappa)>350$.