In diode-pumped solid-state laser system, the performance of pumped coupling system directly determines the output power and the beam quality of laser. we report a pump coupling system for sandwich structured slab gain medium. Image relaying along the slow axis is used to obtain the uniform distribution of pumping light in the slab width direction and the methods of spatial multiplexing and polarization multiplexing are used to increase the density of pump power. When the pump power is 11.2kW, the continuous-wave output power of 4.55kW is obtained through the plane-parallel resonator. Meanwhile, the influence of the methods of spatial/polarized composite splicing on the pump efficiency of the pump coupling system is analyzed, and the experiment results provide the basis for optimization design to high power slab laser.
A compact, high power and high beam quality laser diode stacks partially end-pumped
quasi-continuous wave slab laser with hybrid resonator is demonstrated. Using this
configuration, with Nd:YVO4 as the slab gain media, 101 W output power is obtained
when the pumping power is 216.5W with the repetition of 1kHz, the optical-to-optical
efficiency and slope efficiency are 46.7% and 51.14%, respectively. The beam quality
M2 factors in the unstable direction and the stable direction are 1.36 and 1.56
respectively at the output power of 101 W.