Eur. Phys. J. D (2014) 68: 138
https://doi.org/10.1140/epjd/e2014-40783-5

Regular Article

Entanglement generation under feedback control in dispersive regime

¹ Department of Physics, Harbin Institute of Technology, Harbin 150001, P.R. China
² Department of Electronic Information Engineering, Nanchang University, Nanchang 330031, P.R. China

^a Present address: Department of Physics, Harbin Institute of Technology, Harbin 150001, P.R. China
^b e-mail: stliu@hit.edu.cn

Received: 11 December 2013
Received in final form: 9 March 2014
Published online: 5 June 2014

Abstract

The entanglement generation in a system of two atoms dispersively coupled to a damped cavity mode and driven by a classical field is investigated by using the quantum-jump-based feedback control. We demonstrate that the entanglement of the two atoms can be significantly enhanced and a steady state of antisymmetric Bell state can be obtained. We focus on the role of classical driving, and verify that the laser driving results in a global steady state which can be reached in the whole atomic subspace, but it can only be reached from some special initial states without laser driving. Therefore the system with classical driving is more robust against spontaneous emission and non-unit detection efficiency. Numerical results demonstrate that the maximal entanglement can be obtained for a wide range of parameters.