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Open Physics

Robust control and preservation of quantum steering, nonlocality, and coherence in open atomic systems

K. Berrada, Abdelaziz Sabik

Published Jan 1, 2025• 0 citations
Publisher

Abstract

Abstract We investigate the robustness of Einstein–Podolsky–Rosen (EPR) steering, nonlocality, and quantum coherence in a bipartite atomic system coupled to cavity fields under the influence of decoherence. The system consists of two non-interacting atoms, where each atom is confined within a cavity that interacts with another cavity field, which plays a crucial role in governing the dynamical evolution of two atoms. Through a combination of analytical and numerical investigations, we demonstrate that quantum steering, Bell nonlocality, and coherence can be not only preserved but also enhanced by appropriately tuning the cavity–cavity interaction strength, effectively mitigating environmental decoherence and extending the coherence lifetime of the system. Our results reveal that, under optimal conditions, steering, nonlocality, and coherence remain resilient against decoherence over extended timescales. These findings offer valuable insights into the controlled manipulation of quantum resources in open quantum systems and have significant implications for quantum information processing and secure communication technologies.

DOI
10.1515/phys-2025-0178

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By using the Born Markovian master equation, we study the relationship among the Einstein-Podolsky-Rosen (EPR) steering, Bell nonlocality, and quantum entanglement of entangled coherent states (ECSs) under decoherence. We illustrate the dynamical behavior of the three types of correlations for various optical field strength regimes. In general, we find that correlation measurements begin at their maximum and decline over time. We find that quantum steering and nonlocality behave similarly in terms of photon number during dynamics. Furthermore, we discover that ECSs with steerability can violate the Bell inequality, and that not every ECS with Bell nonlocality is steerable. In the current work, without the memory stored in the environment, some of the initial states with maximal values of quantum steering, Bell nonlocality, and entanglement can provide a delayed loss of that value during temporal evolution, which is of interest to the current study.