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The analysis of the thermal effects of double-slab Nd:YAG laser medium

A novel scheme of the face-pumped double-slab Nd:YAG slab medium cooled by liquid with different temperatures on both sides is proposed. In this structure the thermal distortion of wavefront caused by the non-uniform temperature distribution in the laser gain media can be self-compensated. According to the running mode, the model of the slab medium’s temperature distribution and stress are presented. The analytic solutions for the model are derived. Furthermore, the numerical simulations with pulse pumping energy of 10J and repetition frequencies of 500Hz and 1000Hz are calculated for Nd:YAG laser medium. The simulation results show that the temperature gradient remains the approximative linearity, and the heat stress is in the range of stress extremes. Then the absorption coefficient is also discussed. The result indicates that the doped concentration cannot be too larger for the high repetition frequency laser. It has been prove that high repetition frequency, high average output power of the order of kW of Nd:YAG slab laser with high laser beam quality can be achieved in this structure.