Entanglement dynamics of two qubits driven by classical laser field

Abstract

Abstract:

The entanglement dynamics of two two-level atoms, respectively trapped in two independent dissipative single-mode cavities and strongly driven by the classical fields was investigated through solving the master equation analytically by using super operator method. It is found that the entanglement is not related to the initial value of the cavity coherent states. The driving field enhances the entanglement sudden death for small dissipation of the cavity, while it protects the entanglement from sudden death for large dissipation in the presence of strong driving field. These results show that even in the bad cavity (with large decay rate), the entanglement could be free from sudden death with the assistance of classical driving field.

Key words: classical driving field, entanglement dynamics, concurrence, entanglement sudden death

XIAO Qingsheng ZHONG Yangwan LIU Yanyong. Entanglement dynamics of two qubits driven by classical laser field[J]. J4, 2010, 27(5): 558-564.

References

[1] Einsein A, Pdolsky B, Rosen N, Can quantum-mechanical description of physical reality be considered complete? [J] Phys. Rev. 1935, 47: 777-780.
[2] Bennett C H, Brassard G, Crépeau C, et.al., Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels[J] Phys. Rev. Lett. 1993, 70: 1895-1898.
[3] Zhang T, Mo X F, Han Z. F, Guo G C, Extensible router for a quantum key distribution network .[J], Phys. Lett. A 2008, 372: 3957-3960.
[4] Zheng S B, Guo G C, Tunable phase gate for two atoms with an immunity to decoherence. [J] Phys. Rev. A ,2006, 73: 052328.
[5] Kimble H J, Quantum internet. [J] Nature (New York) 2008, 453: 1023-1030.
[6] Zheng S B, Quantum logic gates for two atoms with a single resonant interaction. [J] Phys. Rev. A 2005, 71: 062335.
[7] Cheng C Y, Feng M, Zhang X L, Gao K L, Robust logic gates and realistic quantum computation. [J] Phys. Rev. A , 2006, 73: 032344.
[8] Yu T, Eberly J H, Finite-time disentanglement via spontaneous emission. [J] Phys. Rev. Lett., 2004, 93: 140404.
[9] Yu T, Eberly J H, Quantum open system theory: bipartite aspects. [J] Phys. Rev. Lett, 2006, 97: 140403.
[10] Wang Z C, Effect of the dipole-dipole interaction on entanglement sudden death of atoms in Tavis-Cummings model.[J] Chinese Journal of quantum Electronics(量子电子学报), 2009, 26(6) 681-688 .
[11] Ann K, Jaeger G, Disentanglement and decoherence in two-spin and three-spin systems under dephasing. [J] Phys. Rev. B, 2007, 75: 115307.
[12] Ikram M, Li F L, Zubairy M S, Disentanglement in a two-qubit system subjected to dissipation environments. [J] Phys. Rev. A, 2007, 75: 062336.
[13] Qasimi A A, Jams D F V, Sudden death of entanglement at finite temperature. [J] Phys. Rev. A, 2008, 77: 012117
[14] Deng X J, Fang M F, The periodic death and anabiosis of the entanglement between two moving atoms. [J] Chin. Phys. B, 2008, 17: 3209-3213.
[15] Almeida M P, de Melo F., Hor-Meyll M et. al., Environment-induced sudden death of entanglement [J] Science, 2007, 316: 579-582.
[16] Yönac M, Yu T, Eberly J H, Sudden death of entanglement of two Jaynes--Cummings atoms. [J] J. Phys. B: Mol. Opt. Phys. 2006, 39:S621-625.
[17] Cui H P, Zhou J, Li J G, Shao B, Dynamical behaviour of the entanglement between two spatially separated atoms under the influence of dissipation. [J] J. Phys. B: Mol. Opt. Phys.2007, 40: S143-157.
[18] Zhang J S, Xu J B, Controlling entanglement sudden death in cavity QED by classical driving fields. [J] Eur. Phys. J. D, 2009, 51: 283-288.
[19] Peixoto de Faria J G, Nemes M C, Dissipative dynamics of the Jaynes-Cummings model in the dispersive approximation: Analytical results. [J] Phys. Rev. A, 1999, 59:3918-3922.
[20] Hill S, Wootters W K, Entanglement of a pair of quantum bits. [J] Phys. Rev. Lett, 1997, 78: 5022-5025.