Eur. Phys. J. D (2015) 69: 154
https://doi.org/10.1140/epjd/e2015-50757-8

Regular Article

Manipulating entanglement against dissipation by pre- and post-measurements with initial system-environment correlations

¹ School of Physics, Beijing Institute of Technology, Beijing 100081, P.R. China
² School of Information and Electronic Engineering, Shandong Institute of Business and Technology, Yantai 264000, P.R. China

^a e-mail: zoujian@bit.edu.cn

Received: 17 October 2014
Received in final form: 15 February 2015
Published online: 11 June 2015

Abstract

We consider that two qubits interact with a common structured reservoir and initially there are correlations between the qubit system and the reservoir. By performing local measurements before and after the two qubits undergo decoherence, not only more entanglement can be produced between them at the beginning, but also the produced entanglement can decay more slowly. We focus on investigating the effects of different initial system-environment correlations on the entanglement of the two qubits, and in each case, we obtain the optimal pre- and post-measurement strength that give the maximum amount of entanglement of the two qubits. We also find that the initial quantum correlations would induce much more entanglement than the initial classical correlations, and the induced entanglement can preserve longer in the initial quantum correlation case. The enhancement of the entanglement depends on the evolution time, the decay rate and the initial state.