Modeling Of A High-power Diode Transverse Pumped Cs Vapor Laser MOPA System

Being a new class of laser device, diode pumped alkali vapor lasers (DAPLs) have obtained a rapid development in recent years. DPALs have the advantages of both the solid lasers and the gas lasers which are promising in achieving near-infrared lasers with high power and high beam quality. Additionally, DPALs have some desirable features such as the high quantum efficiency, the good beam quality, and the narrow line-width (up to MHz), which make it has the extensive potential applications in military field, directional energy transmission, material processing field. In recent years, lots of the research teams who carried out studies on DPALs have obtained promising results. Now in order to get higher output power of DPALs, scientists have put more attention on the optimization of the pump sources, the pump structure, the buffer gas and the mode matching between the pump beam and the resonant cavity. However, there are fewer researches on the dynamic mechanism and the characteristics of the transversely pumped alkali vapor laser MOPA system, therefore, it is important to study these two aspects of the MOPA system to get higher output power in DPALs.This paper first briefly introduces the development of DPALs, the research progress, the typical dynamic model and the MOPA systems based on DPALs. Considering the amplification saturation effect and the matching coefficient between the seed beam and the pump beams, two physical models are established to describe the laser amplification and the dynamic processes of single and double transversely diode pumped alkali vapor laser MOPA system. Influences of the pump power, the size of the cell and the working temperature on the laser output power are calculated. The simulation results agree well with the experimental results in literatures. What is more, we simulate the distribution of the pump power in the cell, which shows that the pump power is nonlinear absorbed. Finally we get a set of optimal parameters which have significance for designing an efficient diode pumped alkali vapor laser MOPA system.