囚禁离子内态的相干导致声子场的压缩  

Squeezing of Phonon Fields Induced by Coherence of Internal States of Trapped Ions

作　　者：聂建军[1] 曾浩生[1] 

机构地区：[1]湖南师范大学物理与信息科学学院,中国长沙410081

出　　处：《湖南师范大学自然科学学报》2007年第3期55-59,共5页Journal of Natural Science of Hunan Normal University

基　　金：教育部科学技术研究重点资助项目(206103);湖南省教育厅青年基金资助项目(05B041)

摘　　要：在非Lamb-Dicke近似下,当驱动经典激光场的频率与质心模红边带发生共振时,两个囚禁离子的内态与声子场耦合的动力学可用非线性Jaynes-Cummings模型来描述.当离子的初始内态处于无相干性混合态、振动声子场初始处于真空态时,演化后声子场无压缩性;而当离子的初始内态处于有相干性的迭加纯态、振动声子场初始处于真空态时,演化后声子场将表现出压缩性.在适当的初始条件下,声子场将表现出永久性压缩状态,并且压缩随时间作周期性变化.While the frequency of classical driving filed is resonant to the red-side band of center-of-mass mode and without Lamb-Dicke limit, the dynamics of the internal states of two trapped ions coupled to their phonon filed can be described by a nonlinear Jaynes-Cummings model. When the internal state of trapped ions is initially in a non-coherent mixed state and the Phonon field in a vacuum state, the evolved state of the phonon field does not appear squeezing; However, when the internal state is initially in a coherent superposition pure state and the phonon field in a vacuum state, the evolved state of the phonon field shows squeezing. Under proper initial conditions, the squeezing is persistent and periodic in time.

关 键 词：声子场 相干 压缩 

分 类 号：O413.1[理学—理论物理]