Dicke模型的量子混沌和单粒子相干动力学特性  

Quantum chaos and the dynamic properties of single-particle coherence in Dicke model

作　　者：宋立军[1] 严冬[1] 盖永杰[2] 王玉波[2] 

机构地区：[1]长春大学理学院 [2]长春理工大学理学院,长春130022

出　　处：《物理学报》2010年第6期3695-3699,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10947019);吉林省教育厅科学技术研究计划(批准号:2009237)资助的课题~~

摘　　要：量子化的Dicke模型在非旋波近似条件下表现为量子混沌动力学特征.利用单粒子一阶时间关联函数,通过数值计算详细考察了Dicke模型中单粒子相干动力学特性.结果表明:当初始相干态处在混沌区域时,一阶时间关联函数曲线衰减较快,而当初始相干态处在规则区域时,一阶时间关联函数曲线衰减较慢,单粒子相干动力学对初态具有较强的敏感性,经典混沌抑制量子相干.考察单粒子相干动力学在相空间的平均演化性质,得到一种较好的量子经典对应关系.最后研究了相空间单粒子相干的整体动力学性质,更好地揭示了相空间的混沌和规则结构.The Dicke model displays quantum chaotic dynamic properties in the without-rotating-wave approximation. We explore the dynamic properties of the single-particle coherence in Dicke model by using the first-order temporal correlation function and numerical simulation. The results reveal that the first-order temporal correlation function decays very rapidly when the initial coherent state is centered in chaotic regions,but rather slowly when the initial coherent state is centered in regular regions. This indicates that the single-particle coherence is highly sensitive to initial states,and the classical chaos suppresses quantum coherence. The mean single particle coherence during the evolution is studied,and a better quantum-classical correspondence is obtained. Finally,the dynamics of single-particle coherence in the whole phase space is investigated,which reveals the chaotic and regular structures of the phase space more clearly.

关 键 词：DICKE模型 非旋波近似 量子混沌 单粒子相干 

分 类 号：O413.1[理学—理论物理] O415.5[理学—物理]