Y模型四能级原子辅助光力学系统的多稳现象

本文对Y模型四能级原子辅助光力学系统的稳态特性进行了研究.结果发现,构成复合光力学系统的振动腔镜和被束缚在腔内的原子系综将随着弹簧劲度系数的减小,由单稳态过渡到多稳态.在劲度系数很大时,振动腔镜对整个光力学系统几乎无作用,光力学系统和处在腔中的原子系综都将出现一个稳态解.而当劲度系数足够小时,振动腔镜的稳态位移出现了多稳现象,随之对处于光力学腔中的原子系综的稳态行为也产生了影响,不但使得原子系综的极化率呈现出多个稳态解,同时使得腔中的原子系综对探测光的吸收和色散也发生了相应的变化.同时发现,通过调节劲度系数的取值可以控制整个系统稳态解的个数.这些研究结果在精密测量或量子信息处理等方面具有潜在应用价值.

Multistable phenomenon of the Y-type four-level atom-assisted optomechanical system

We have studied the steady-state properties of a hybrid optomechanical system, where a Y-type four-level atomic ensemble is confined in a microcavity with an oscillating mirror in one end. We find that the hybrid system will have multistability for the oscillating mirror and the confined atoms as the elastic coefficient of the spring decreases. When the elastic coefficient is very large, the oscillating mirror hardly affects the optomechanical system, therefore the system and the atomic ensemble have a single steady-state solution. However, when the elastic coefficient is small enough, the multiequilibrium positions of the oscillating mirror will be found, and the steady-state behaviors of the atomic ensemble confined in the microcavity may be affected. As a result, the susceptibility of the atomic ensemble will have multiple steady-state solutions and the probe absorption and dispersion will be changed as well. It has also been found that the number of steady-state solutions of the entire system could be controlled by changing the value of the elastic coefficient. These results may have potential applications in the area of high-precision quantum measurement and quantum information processing.
Keywords： Y-type four-level atoms optomechanical system optical multistability