本文研究了一个由光纤连接的两个法布里-帕罗腔所组成的耦合光机械系统,每一个腔都是由一个固定的镜子和一个移动的镜子组成,移动的镜子可以看作机械振子,同时,这两个腔模都被经典激光场驱动,则在腔场与腔场之间,镜子与腔场之间,以及经典激光场和腔场之间都会产生相互作用。通过变换绘景、绝热剔除、旋波近似忽略高频项等量子光学的处理方法消除哈密顿中的两个腔模,得到了两个声子模之间有效的哈密顿;在假设两个机械振子的初态是相干态的情况下,解析出两个耦合的机械振子能够进行态交换;最后,为了验证解析结果,数值模拟了系统量子态的保真度,模拟结果表明,解析结果与数值模拟是自洽的,两个机械振子之间可以周期性地进行态交换。
This paper investigates a coupled cavity optomechanical system consisting of two Fabry-Perot cavities and the two cavities are coupled via an optical fiber. Every cavity is made of one fixed mirror and a movable mirror, and the movable mirror can be regarded as a mechanical oscillators. Meanwhile, the two cavity modes are driven by classical laser fields. So, the interaction is inevitable between cavities, cavity and moving mirror, cavity and classical field. Firstly, in order to eliminate the two cavity fields, an effective Hamiltonian of the two phonon modes is derived by means of picture transformation, adiabatic eliminating, and rotating wave approximation ignoring the high frequency items, etc. Secondly, if the two mechanical oscillators initially are in coherent states, the coupled mechanical oscillators can be used to transmit state. Finally, in order to verify the analytical result, the fidelity of quantum state is numevically simulated, the result shows that the quantum state can be transferred periodically between the two mechanical oscillators, which is the same as the analytical result.