多光子J-C模型中频率随时间变化场的压缩效应  

Squeezing Effects of Field with a Time-Varying Frequency in the Multiphoton Jaynes-Cummings Model

作　　者：卢道明[1] 

机构地区：[1]武夷学院电子工程系,福建武夷山354300

出　　处：《光子学报》2009年第7期1840-1845,共6页Acta Photonica Sinica

基　　金：福建省自然科学基金(T0650013)资助

摘　　要：利用多光子J-C模型,考虑场频率随时间以正弦函数形式作小量变化,在旋波近似下,研究了二能级原子通过多光子跃迁与单模辐射场相互作用系统中场的压缩效应.利用数值计算方法讨论了场频率变化的幅值和角频率、以及光场强度对场压缩效应的影响.结果表明:随场频率变化的幅值增大,场压缩效应增强;随光场初始平均光子数的增加,场压缩效应减弱.场正交分量的均方涨落随时间的演化受场频率随时间正弦函数形式变化的调制,场频率变化的幅值越大调制作用越强.Using the muhiphoton Jaynes-Cummings model,the squeezing effect of the field in the system of a two-level atom interacting with the single mode coherent field through mutiphoton transition was studied. The frequency of the field varying with time in the form of sine was considered. The influences of amplitude and angular frequency of the field-frequency variation on squeezing effects of the field were discussed by numerical calculations. The influences of mean photon number of the field on squeezing effects of the field were also discussed. Calculation results indicate that the squeezing effects of field strengthens with the increase of the amplitude u of field-frequency variation and weaken with the increase of mean photon number of the field. The time-evolution behavior of quadrature squeezing function Q1 is modulated by the field-frequency variation. The modulation intensity is enchanced with the increase of the amplitude u of field-frequency variation, and when the amplitude u of field-frequency variation is larger than a fixed value, the time-evolution of quadrature squeezing function Q1 will display quasi-periodicity oscillation behavior. Its oscillation frequency agrees with the angular frequency of field-frequency variation.

关 键 词：二能级原子 J—C模型 频率变化场 压缩效应 

分 类 号：O431.2[机械工程—光学工程]