Rank dependence of entanglement sudden death of a two-qubit system in a thermal reservoir

• Published in: Journal of optics (New Delhi) Vol. 48; no. 4; pp. 474 - 478
• Main Authors: Namitha, C. V., Paulson, K. G., Satyanarayana, S. V. M.
• Format: Journal Article
• Language: English
• Published: New Delhi Springer India 01.12.2019; Springer Nature B.V
• Subjects: Dependence; Dipoles; Entangled states; Evolution; Lasers; Optical Devices; Optics; Photonics; Photons; Physics; Physics and Astronomy; Quantum entanglement; Qubits (quantum computing); Research Article; Reservoirs; Decoherence; Markovian process; Quantum entanglement; Thermal reservoir
• DOI: 10.1007/s12596-019-00563-9
• ISSN: 0972-8821

Entanglement sudden death and revival of entanglement are generic features of the evolution of entangled quantum systems interacting with a thermal reservoir. We investigated the evolution of mixed entangled states of different ranks of two spatially separated qubits interacting through dipole forces and in contact with a common finite temperature photon bath. For a fixed initial concurrence, lower rank initial states exhibit ESD at later times. ESD time increases with increase in initial concurrence for a given mean number of photons, N in a bath. Further, ESD time decreases with increase in N . The choice of low rank mixed state with higher entanglement and low N of the bath can delay or even avoid ESD.