微波场作用下三能级原子系统的无反转光放大

研究了外加微波场作用下三能级原子系统的无粒子数反转放大特性. 通过求解系统的密度矩阵方程得到其探测吸收谱. 结果表明, 介质对探测场的吸收呈现多峰结构, 并且在强微波驱动场的作用下, 特定范围内出现了明显的负吸收(即光放大). 进一步定量分析各能级粒子数布居随作用场强度的变化, 揭示出该三能级原子系统呈现无粒子数反转光放大的规律. 最后, 采用缀饰态理论对探测吸收特性做出了准确的解释.

Amplification without population inversion in tree-level system driven by an additional microwave field

In this paper, we investigate the spectrum properties of the lasing without population inversion in a three-level atomic system under an action of an externally applied microwave field. The probed absorption spectrum is obtained by solving the density matrix equation of this system. The results show that the absorption profile has a multi-peak structure, and exhibits obviously negative absorption (light amplification) in a specific range under the action of strong microwave field. The characteristic of the light amplification without population inversion according to the three level atomic system is demonstrated by the quantitative analysis of populations related to the probe levels.