Eur. Phys. J. D (2012) 66: 24
https://doi.org/10.1140/epjd/e2011-20242-9

Regular Article

Quantum discord dynamics of two-qubit system in a quantum spin environment

¹ College of Physics and Electronic Information Science, Tianjin Normal University, Tianjin 300387, P.R. China
² School of Science, Hebei University of Technology, Tianjin 300401, P.R. China
³ School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, P.R. China

^a e-mail: guojinliang80@163.com

Received: 29 April 2011
Received in final form: 2 December 2011
Published online: 31 January 2012

Abstract

We study the dynamics of quantum discord of two-qubit system in a quantum spin environment at finite temperature in the thermodynamics limit. Special attention is paid to the difference between the entanglement and quantum discord when considering the influences of the environment temperature and the initial system states. We show that in the same range of the physical parameters, when the system states behave no entanglement or entanglement sudden death, the quantum discord keeps nonzero. So the quantum discord is more robust than entanglement under this decoherence environment. Furthermore, we also illustrate that we can tune the parameters related to the system and the environment to suppress the decay of quantum discord.