The advantage of two-photon pumped alkali vapor lasers (TPALs) is the realization of cascading and coaxial output of blue-violet photons and midinfrared photons, which can be used in many fields of scientific research, such as multi-wavelength detection, underwater communication, and photoelectric countermeasures.

In a study published in IEEE Journal of Quantum Electronics, a research group led by Prof. CHEN Fei from the Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP) of the Chinese Academy of Sciences (CAS) proposed a three-dimensional theoretical model of single-wavelength two-photon pumped Rb-vapor laser.

Base on the coupling-wave equation and rate equation, a three-dimensional computational model of continuous-wave (CW) single-wavelength pumped two-photon absorption alkali vapor laser was established. Thereafter the effects of the parameters of the high-power CW laser diode-pumped Rb-TPAL such as the temperature, vapor cell length, pump waist, vapor cell transmission, and output mirror reflectance on the blue laser power, efficiency, and pumping threshold were investigated.

The three-dimensional computational model is established for the first time, and the calculated results are in good agreement with the measurements. Finally, the established relationship was used to obtain the optimization results: when the pumping power reaches 500 W, the output power reaches up to 43.64 W and the efficiency is 8.73%.

The model and simulation results provide an effective way to design a high power TPAL system.