Chinese Physics B

Entanglement and non-Markovianity of a spin- S system in a dephasing environment

Zi-Long Fan, Jing Tian, Hao‐Sheng Zeng

Published May 30, 2014• 8 citations

Abstract

We study the entanglement (measured by negativity) evolution and the non-Markovianity for the dynamical process of a spin-S system embedded in dephasing environments. The exact analytical solution is presented, which shows that the decoherence function governs the evolutions of coherence, entanglement, and the non-Markovianity of the corresponding dynamical processes. For Ohmic and sub-Ohmic reservoirs, the negativity decreases monotonically in time and the corresponding dynamics is Markovian. While for super-Ohmic reservoirs with non-monotonic decoherence function, the negativity appears as the phenomenon of revival and the corresponding dynamics is non-Markovian. The relation between non-Markovianity and the system dimension is studied.

DOI: 10.1088/1674-1056/23/6/060303

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