为了研究碱金属铷蒸气激光器中新的波长输出情况及其可能的应用,在铷原子系统中通过5 2S1/2→6 2D5/2 和5 2S1/2→6 2D3/2的双光子激发和四波混频过程产生358.7 nm、359.1 nm、420.3 nm和421.7 nm四种波长的激光输出,得出了6 2D5/2和6 2D3/2能级的最佳共振位置以及共振线宽,研究了产生的四波混频激光信号强度随体系温度和泵浦光单脉冲能量的变化情况,发现了当体系温度高于185 ℃时6 2D5/2→6 2P1/2的反常跃迁情况并给出了初步解释。实验结果表明,这种通过铷蒸气四波混频产生蓝紫激光的技术可以为海洋资源探测、高密度信息存储及水下激光通信等领域提供一种新的激光光源。

In order to study the new wavelength output of the alkali metal rubidium vapor laser and its possible applications, the two-photon excitation and four-wave mixing process of 5 2S1/2→6 2D5/2 and 5 2S1/2→6 2D3/2 in the rubidium atomic system produced laser output with four wavelengths of 358.7 nm, 359.1 nm, 420.3 nm, and 421.7 nm, obtained the best resonance position and resonance linewidth of 6 2D5/2 and 6 2D3/2 energy levels, and studied the generated four-wave mixing laser. The signal intensity changes with the temperature of the system and the energy of the single pulse of the pump light. An abnormal transition of 6 2D5/2→6 2P1/2 is found when the system temperature is higher than 185 ℃ and a preliminary explanation is given. Experimental results show that this technology of generating blue-violet lasers through four-wave mixing of rubidium vapor can provide a new laser source for marine resource exploration, high-density information storage, and underwater laser communications.