Thermal effects on bipartite and multipartite correlations in fiber coupled cavity arrays

TL;DR

This paper studies how thermal fluctuations in fibers affect quantum correlations in fiber-coupled cavity arrays, revealing that discord persists longer than entanglement under thermal noise, with implications for quantum information processing.

Contribution

It introduces a master equation approach to analyze thermal effects on bipartite and multipartite quantum correlations in fiber-coupled cavity arrays, highlighting thermal blockade phenomena.

Findings

Thermal fluctuations can block entanglement generation between directly connected qubits.

Quantum discord can be generated and maintained longer than entanglement under thermal noise.

Longer chains of qubits exhibit more robust bipartite correlations against thermal effects.

Abstract

We investigate the thermal influence of fibers on the dynamics of bipartite and multipartite correlations in fiber coupled cavity arrays where each cavity is resonantly coupled to a two-level atom. The atom-cavity systems connected by fibers can be considered as polaritonic qubits. We first derive a master equation to describe the evolution of the atom-cavity systems. The bipartite (multipartite) correlations is measured by concurrence and discord (spin squeezing). Then, we solve the master equation numerically and study the thermal effects on the concurrence, discord, and spin squeezing of qubits. On the one hand, at zero temperature, there are steady-state bipartite and multipartite correlations. One the other hand, the thermal fluctuations of a fiber may blockade the generation of entanglement of two qubits connected directly by the fiber while the discord can be generated and stored for a long time. This thermal-induced blockade effects of bipartite correlations may be useful for quantum information processing. The bipartite correlations of a longer chain of qubits is more robust than a shorter one in the presence of thermal fluctuations.