## Enhancing quantum discord in cavity QED by an added nonlinear Kerr-like medium |

JOSA B, Vol. 28, Issue 12, pp. 2966-2973 (2011)

http://dx.doi.org/10.1364/JOSAB.28.002966

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### Abstract

We investigate the quantum discord dynamics of two noninteracting two-level atoms, each trapped in a single-mode optical cavity which is filled with a nonlinear Kerr-like medium. It is found that quantum discord vanishes only asymptotically although entanglement disappears suddenly during the time evolution. Furthermore, we explore the influence of the nonlinear Kerr-like medium on the dynamics of quantum discord, quantum mutual information, and classical correlation of two atoms. It is shown that the amount of quantum discord, quantum mutual information, and classical correlation of two atoms can be improved by adjusting the value of the Kerr medium. Finally, we also study the effect of phase dissipation on this system by making use of the Monte Carlo wavefunction method.

© 2011 Optical Society of America

**OCIS Codes**

(270.2500) Quantum optics : Fluctuations, relaxations, and noise

(270.5585) Quantum optics : Quantum information and processing

**ToC Category:**

Quantum Optics

**History**

Original Manuscript: April 11, 2011

Revised Manuscript: July 18, 2011

Manuscript Accepted: September 24, 2011

Published: November 23, 2011

**Citation**

Qi-Liang He and Jing-Bo Xu, "Enhancing quantum discord in cavity QED by an added nonlinear Kerr-like medium," J. Opt. Soc. Am. B **28**, 2966-2973 (2011)

http://www.opticsinfobase.org/josab/abstract.cfm?URI=josab-28-12-2966

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