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Springer proceedings in physics

Exploring Entanglement and Quantum Fisher Information in a System of Two Superconducting Qubits Subjected to Thermal Noise

Mourad Benzahra, Mostafa Mansour

Published Oct 10, 2025• 0 citations
Publisher

Abstract

Abstract This study explores the dynamics of a two-qubit superconducting charge system, a prevalent technology in quantum computing. We utilize logarithmic negativity and local quantum Fisher information to gauge the entanglement and correlations within this system. Our findings indicate a significant influence of temperature on the system, leading to a reduction in both measures. However, adjusting system parameters can enhance these quantum quantifiers. Furthermore, we note that the local quantum Fisher information exhibits greater resilience to temperature-induced degradation compared to logarithmic negativity.

DOI
10.1007/978-3-031-88933-2_19

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Abstract We employ entanglement negativity, local quantum uncertainty (LQU), and local quantum Fisher information (LQFI) to characterize thermal entanglement between two XYZ-Heisenberg-qubit states under the influence of Dzyaloshinsky-Moriya(DM) and Kaplan-Shekhtman-Entin-Wohlman-Aharony (KSEA) interactions, as well as a magnetic field and thermal equilibrium temperature. A comparative examination reveals similar behaviors among these correlation measures. For the antiferromagnetic scenario, we observe that increasing the DM interaction parameter D z enhances thermal entanglement. Conversely, in the ferromagnetic case, the behavior of thermal entanglement differs with varying D z . Additionally, employing Kraus operators, we explore the performance of these quantifiers under decoherence. Notably, LQFI exhibits greater robustness than negativity and LQU, even displaying a frozen phenomenon at some time under dephasing effects.