稳态V型和Λ型无粒子数反转激光增益的比较研究

在相应参量取值相同的情况下,利用数值模拟的方法对比研究了封闭的V型和Λ型原子系统稳态增益随相干光场失谐量的变化规律.研究发现,这两种系统的稳态探测激光增益随探测激光场失谐量的变化曲线具有相似的形状,但数值上存在差异.这一现象与两种系统的原子相干性与粒子数分布的特点直接相关.另外,还发现驱动激光失谐及由于自发辐射诱导相干导致的原子相干性的增强能显著影响探测激光增益. 关键词： 无粒子数反转激光 失谐 原子相干性 粒子数分布     

Noticeable positive Doppler effect on optical bistability in an N-type active Raman gain atomic system

We theoretically investigate the Doppler effect on optical bistability in an N-type active Raman gain atomic system inside an optical ring cavity.It is shown that the Doppler effect can greatly enhance the dispersion and thus create the bistable behaviour or greatly increase the bistable region,which has been known as the positive Doppler effect on optical bistability.In addition,we find that a positive Doppler effect can change optical bistability from the hybrid dispersion-gain type to a dispersive type.