Dephasing effects on quantum correlations and teleportation in presence of state dependent bath

• Published in: Modern physics letters. B, Condensed matter physics, statistical physics, applied physics Vol. 38; no. 6
• Main Authors: Rashid, Mehboob, Lone, Muzaffar Qadir, Ganai, Prince A.
• Format: Journal Article
• Language: English
• Published: Singapore World Scientific Publishing Company 29.02.2024; World Scientific Publishing Co. Pte., Ltd
• Subjects: Bosons; Correlation; Quantum entanglement; Quantum phenomena; Quantum teleportation; Qubits (quantum computing); Time dependence; Time measurement; teleportation; negativity; fidelity; discord; Dephasing
• ISSN: 0217-9849; 1793-6640
• DOI: 10.1142/S0217984923502457

Quantum information protocols are often designed in the ideal situation with no decoherence. However, in real setup, these protocols are subject to the decoherence and thus reducing fidelity of the measurement outcome. In this work, we analyze the effect of state-dependent bath on the quantum correlations and the fidelity of a single qubit teleportation. We model our system-bath interaction as qubits interacting with a common bath of bosons, and the state dependence of the bath is generated through a projective measurement on the joint state in thermal equilibrium. The analytic expressions for the time evolution of entanglement, discord and average fidelity of quantum teleportation are calculated. It is shown that due to the presence of initial system-bath correlations, the system maintains quantum correlations for long times. Furthermore, due to the presence of finite long-time entanglement of the quantum channel, the average fidelity is shown to be higher than its classical value.