Time-invariant discord: high temperature limit and initial environmental correlations

Author(s)

Tabesh, F. T. ^{[1, 2]} ; Karpat, G. ^[3] ; Maniscalco, S. ^{[2, 4]} ; Salimi, S. ^[1] ; Khorashad, A. S. ^[1]

Affiliation

^[1] Univ Kurdistan, Dept Phys, POB 66177-15175, Sanandaj - Iran

^[2] Univ Turku, Dept Phys & Astron, Turku Ctr Quantum Phys, Turku 20014 - Finland

^[3] Izmir Univ Econ, Dept Phys, Fac Arts & Sci, TR-35330 Izmir - Turkey

^[4] Aalto Univ, Sch Sci, Dept Appl Phys, Ctr Quantum Engn, POB 11000, Aalto 00076 - Finland

• Document type: Journal article
• Source: QUANTUM INFORMATION PROCESSING; v. 17, n. 4 APR 2018.
• Web of Science Citations: 0

Abstract

We present a thorough investigation of the phenomena of frozen and time-invariant quantum discord for two-qubit systems independently interacting with local reservoirs. Our work takes into account several significant effects present in decoherence models, which have not been yet explored in the context of time-invariant quantum discord, but which in fact must be typically considered in almost all realistic models. Firstly, we study the combined influence of dephasing, dissipation and heating reservoirs at finite temperature. Contrarily to previous claims in the literature, we show the existence of time-invariant discord at high temperature limit in the weak coupling regime and also examine the effect of thermal photons on the dynamical behavior of frozen discord. Secondly, we explore the consequences of having initial correlations between the dephasing reservoirs. We demonstrate in detail how the time-invariant discord is modified depending on the relevant system parameters such as the strength of the initial amount of entanglement between the reservoirs. (AU)

• FAPESP's process: 12/18558-5 - Studying the monogamic relations between entanglement and quantum correlations
• Grantee: Goktug Karpat
• Support Opportunities: Scholarships in Brazil - Post-Doctoral