Quantum phase transition of nonlinear light in the finite size Dicke Hamiltonian
Quantum phase transition of nonlinear light in the finite size Dicke Hamiltonian
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DOI：
10.1364/josab.27.002443
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发表时间：
2010-05
影响因子：
1.9
通讯作者：
B. M. Rodr'iguez-Lara;Ray-Kuang Lee
中科院分区：
文献类型：
--
作者：
B. M. Rodr'iguez-Lara;Ray-Kuang Lee
研究了N个二能级系统系综与简并参量过程相互作用的量子相变，该过程可用有限尺寸迪凯哈密顿量加上反转场和二次场项来描述.在弱耦合和强耦合情况下，导出了临界耦合值及其相应的可分基态的解析封闭形式。通过数值分析，证明了二能级系统系综与光场之间以及中等耦合情况下系综分量之间存在二体纠缠。在有限尺寸下，我们的结果也表明了压缩场和压缩原子系综的共存。
We study the quantum phase transition of an N two-level system ensemble interacting with an optical degenerate parametric process, which can be described by the finite size Dicke Hamiltonian plus counter-rotating and quadratic field terms. Analytical closed forms of the critical coupling value and their corresponding separable ground states are derived in the weak and strong coupling regimes. The existence of bipartite entanglement between the two-level system ensemble and photon field as well as between ensemble components for moderate coupling is shown through numerical analysis. Given a finite size, our results also indicate the co-existence of squeezed fields and squeezed atomic ensembles.