激光诱导的四能级系统电子布居转移

Laser induced four-level system population transfer

受激拉曼绝热通道(STIRAP)为我们提供了一种有效转移原子与分子中电子布居的方法。采用数值方法系统地分析了不同的四能级系统在受激拉曼迁移过程中电子布居的转移情况,计算了各种系统处于双光子共振和共振失谐时的转移率,并且讨论了在不同情况下第四能级对转移率的影响。计算结果表明,对于许多原子或分子系统,获得高的转移率所必须满足的条件是非常严格的,而有些四能级系统根本就不能获得高的转移率。

Stimulated-Raman-adiabatic-passage(STIRAP)process provides an effective technique to transfer electron population for both atoms and molecules. In this paper, the population transfer in different four-level systems through stimulated-Raman-adiabatic-passage is considered using numerical method,the transfer efficiency on two-photon resonance and off two-photon resonance is calculated and the influence of the fourth level on the transfer efficiency under different conditions is analyzed. It appears that, for many atomic or molecular systems, the criteria which must be met in order to achieve high transfer efficiency are very stringent and for certain four-level systems, it is impossible to achieve high transfer efficiency.