超冷V型三能级原子注入的微脉塞的光谱性质

Spectrum of the Micromaser Injected with Ultracold V-Type Three-Level Atoms

建立了超冷V型三能级原子注入的微脉塞的量子理论。首先推导出腔场约化密度算符随时间演化的主方程 ,并由此出发着重研究了微脉塞腔场的光谱性质。结果表明 ,与用超冷二能级原子或用热的二能级和三能级原子注入的微脉塞的光谱相比 ,用超冷V型三能级原子注入的微脉塞具有新的光谱性质 ,对某些腔长 ,线宽可被突然加宽 ,腔场也发生大的频移。不同的原子相干性甚至可以使腔场频率发生方向相反的频移。另一方面 ,原子质心动量对光谱也有影响 ,表现在线宽和频移随质心动量减小而减小。

The spectrum of the micromaser injected with ultracold V-type three-level atoms is studied. It is found that this kind of micromaser shows new spectra properties different from those of the micromaser injected with ultracold two-level atoms and the traditional micromaser injected with thermal two or three-level atoms. The main conclusions are that the line width can be broadened and the frequency can be either red-shifted or blue-shifted. Atom coherence influences the spectrum and even can make the frequency shift toward opposite directions. On the other hand, the line width and frequency shift of the spectrum decrease with the center of mass momentum of the atoms.