Side-pumped Nd:YAG Disk Laser

Comparing with traditional all-solid laser, thin-disk laser has two significant advantages. One advantage is the direction of cooling flow is the same with cavity resonant oscillation of light, making cooling flow similar to one-dimensional heat distribution, which effectively reduces the thermal lens effect; the other is the large cooling area of gain medium for disc-laser, making the heat dissipation power density of the material being pumped per area very small. These two advantages make the side-pumped thin-disk laser have very high power and good beam quality.Disk laser has two kind of pump style, side-pumping and end-pumping. The end-pump mode use fiber-coupled beam, generating homogeneous beam distribution. After multiple reflections, about 90% pumping light can be absorbed. The side-pump mode is making the pumped light into the crystal directly. Compared to end-pump mode, the side-pump mode not only has very simple structure, no coupled fiber and high efficiency, but also can reduce the heat dissipation power density of the material per area by enlarging the area of gain medium, which highlight the development potential of disc-laser.By numerical simulation of the light distribution in crystal, we achieve the crystal size under the situation of uniform distribution of light. Then after bonding, film coating of the bonded crystal, and soldering on the copper heat sink, we finally realize the side-pumped thin disk-laser. Besides, we designed different experiments, for optimizing the various parameters, and at the same time, related theoretical research is done. Finally, we achieved the laser output with 33.5% of opt.-opt. effect, 230W of peak power and 21.6 mm*mrad of the beam parameter product.