Numerical simulation of pumping uniformity and thermal effects of LD end-pumped slab amplifier

In order to obtain high bright and high-average-power output of diode pumped solid-state laser,the temperature distribution in the laser medium and thermal lens effects,essential for improving the laser performance,were analyzed.With the help of ZEMAX software,the distribution of pump light in gain material was analyzed when end-pumped by high power LD. Simulation results showed that the optical field distribution was uniform with that in end-pumped structure.Then applying the pump power density in gain material to LASC-AD software,under the condition of the amplifier before and after being seeded, with the pump power of 2400W,the maximum temperature differences were 68℃ and 54.7℃ respectively,maximum thermal stress were 90N/mm2 and 67N/mm2 respectively.Therefore,when the pumping power was lower than 2400W,there was no threat for the laser gain medium under the entire operation of the amplifier.The simulation results have a certain reference value for the design of high-power diode-pumped slab amplifier.