Simulations for transversely diode-pumped metastable rare gas lasers

The transverse pumping geometry simplifies the laser system design by separating pump and laser beams and providing space for multiple diode laser pump sources with poor beam quality. A transverse pumping double-pass model for metastable rare gas lasers is presented in this paper, in which some intra-cavity information can be obtained. The comparison with Yang’s longitudinally pumped calculation results demonstrated the validity of our model. Several important factors having influence on optical conversion efficiency are simulated and discussed. Simulation of the effects of the required plasma size in transverse pumping model shows that a small size of 0.3 cm×10 cm×10 cm is capable of emitting 9 kW with an optical conversion efficiency over 55% and a megawatt-class output would only need an active medium of several liters if the metastable atoms concentration reaches 3×1013 cm−3.