Abstract

The population kinetics of a two-level system has been theoretically investigated taking into account the transfer of spontaneous radiation under continuous optical pumping. It is shown that, when the photon mean free path in a resonantly absorbing medium is smaller than the characteristic size of this medium or comparable to it, the spontaneous radiation may become an additional pump source. The contribution of spontaneous photons to the kinetics of level has been considered within two approaches. The first approach consists of solution of the radiation transfer equation within the diffusion approximation. The second approach is related to solution of the Biberman–Holstein equation.

中文翻译：

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两级系统中共振辐射的传递与俘获

摘要

理论上已经研究了两级系统的种群动力学，其中考虑了连续光泵浦下的自发辐射转移。结果表明，当共振吸收介质中的光子平均自由程小于该介质的特征尺寸或与之相当时，自发辐射可能会成为额外的泵浦源。在两种方法中已经考虑了自发光子对能级动力学的贡献。第一种方法是在扩散近似内求解辐射传递方程。第二种方法与Biberman-Holstein方程的求解有关。