在缀饰场中四能级“Ladder”系统的布局数转移

利用"反直觉"频率啁啾激光脉冲分析了偶能级ladder系统的布局数迁移,其中在缀饰激光场作用下N-2个中间态进行耦合.作为偶能级ladder系统的代表,我们着重分析了四能级ladder系统.研究发现如果缀饰激光场足够强且发生共振,则在能级1和能级4之间发生完全布局数迁移必须要求有一个恰当的脉冲叠加面积,调谐pump激光和stokes激光,使其中一个缀饰中间态发生共振,则可以使这个四能级系统简化为三能级系统.

Population Transfer in Four-Level Ladder System Assisted by Dressing Fields

Even-level ladder system has been analyzed for population transfer by counterintuitive frequency-chirped laser pulse, in which intermediate states are strongly coupled by dressing laser field. The specific analysis for the four-level ladder system has been carried out by using a dressed-state picture, as representatives for even- -system. It is found that a well-controlled pulse area is required for complete population transfer from if the dressing field is sufficiently strong and on resonance. And it is essential to detune the pump and Stokes lasers so that one of the dressed intermediate states is on resonance, leading to the reduction of the whole system to the three-level system