LAUSR

Multiple deleterious processes occurring in alkali vapor laser amplifiers can significantly degrade their performance. To study that, a theoretical model of a side-pumped flowing-gas alkali vapor amplifier is set up, which mainly takes into account the effect of saturation, amplified spontaneous emission, quenching, energy pooling, photoexcitation, Penning ionization, photo-ionization, and ion recombination. Influences of powers of the pump and seed laser, the velocity of gas mixture flow, and the cell length on the deleterious processes are also simulated. The results show that the influence of deleterious processes can be increased when pump power enhances. But it can be effectively restrained with relatively strong seed laser power and optimized operating parameters. The total percent drop in amplified laser power is about 19.95% at a pump power of 500 W, a seed laser power of 5 W, a saturated flowing velocity of 40 m/s, and an optimized cell length of 7 cm.