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arXiv · 2608.17217

Dynamical protection of quantum steering and fidelity dynamics in double Jaynes-Cummings model

Koushik Mandal·Chitra Rangan·Shohini Ghose
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Abstract

We investigate the dynamics of Einstein-Podolsky-Rosen (EPR) steering in a double Jaynes-Cummings model, where two initially entangled spatially separated two-level atoms in two cavities interact with independent cavity modes. We study how the intrinsic noise in an initial Werner-type state affects the steering dynamics in this type of quantum optical systems. We also analyze the evolution of steering under experimentally relevant conditions, including atom-cavity detuning and dipole-dipole interactions. We find that both detuning and dipole-dipole coupling help reduce steering sudden death in the system. We further identify a direct correlation between steering and state fidelity, revealing a threshold below which steering disappears. This suggests that fidelity can serve as a practical indicator of steerability in cavity QED systems. Our results provide insight into the controllability and robustness of nonclassical correlations in realistic light-matter platforms.

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Koushik Mandal, Chitra Rangan, Shohini Ghose. 2026-08-18. Dynamical protection of quantum steering and fidelity dynamics in double Jaynes-Cummings model. https://arxiv.org/abs/2608.17217

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