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Laser Physics Letters

Quantum discord, entanglement of formation, and JS coherence in hybrid superconducting qubit-cavity system

M Hashem, H Allhibi, F Aljuaydi, A-B A Mohamed

Published Nov 1, 2025• 0 citations
Publisher

Abstract

Abstract This study investigates the dynamics of quantum correlations and coherence in an open hybrid superconducting (SC) qubit-cavity system, focusing on quantum discord (QD), entanglement of formation and JS coherence. The results show that the initial cavity state, Ising interactions, qubit-cavity detuning, and SC qubit-cavity couplings significantly affects the quantum behavior of the system. Furthermore, the study highlights that increasing qubit–qubit interaction coupling via Ising interactions and tuning the qubit-cavity detuning have strong effects on quantum correlations, with QD showing greater resilience compared to entanglement, especially in noisy environments. These results highlight the importance of controlling both the initial cavity state and the interaction strengths to optimize quantum correlations and coherence. The insights gained from this study are a valuable contribution to the development of robust quantum systems that improve strategies for SC quantum processors and the broader field of quantum computing.

DOI
10.1088/1612-202x/adeb61

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