Abstract We investigate the pairwise entanglement and global entanglement in a generalized Jaynes--Cummings model, which can be used to realize Greenberger--Horne--Zeilinger (GHZ) entangled state (Zheng S B 2001 Phys. Rev. Lett.87 230404). Our results show that the W-type entangled states cannot be generated based on the model. The dependences of entanglement on Rabi frequency $\lambda$ and dipole--dipole coupling strength ${\it \Omega}$ are given. It is found that there exists the quantum phase transition when $\lambda={\it \Omega}$. For typical experimental data, the critical temperature for pairwise entanglement is on the order of $10^{-6}$ K. Based on these results, two strategies that overcome decoherence are proposed.
Accepted manuscript online:
PACS:
42.50.Dv
(Quantum state engineering and measurements)
Fund: Project supported by the National
Nature Science Foundation of China (Grant No 10604053).
Cite this article:
Zhang Guo-Feng(张国锋) and Liu Jia(刘佳) Entanglement in a generalized Jaynes--Cummings model 2007 Chinese Physics 16 3595
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.