[22a-A402-1~9] 3.4 Laser system and materials (formerly 3.5)

[22a-A402-5] Development of large YAG single crystal by Top Seeded Melt Growth (TSMG) Method

〇Maki Takahashi¹, Tomotsugu Kinoshita¹, Shohei Asaka¹, Saiko Shimizu¹, Kazuhiro Kawashima¹, Keisuke Mochizuki¹, Hideomi Koinuma² (1.Shinkosha Co. Ltd., 2.SCT Inc.)

Keywords:large single crystal, YAG, TSMG

Large YAG single crystals with high crystal quality were developed for the use of a laser medium especially for high-power laser. The crystals were grown by TSMG method with resistance heating. When YAG crystal was grown by TSMG method, oxygen vacancies formed because of a reduced atmosphere in TSMG chamber, and the crystal growth was disturbed. We improved a thermal circumstance in the chamber, a flow rate of the atmospheric gas, and so on. Then, a large YAG crystal with a diameter around 120 mm was successfully obtained. Yb:0.5-5.0 atomic % doped YAG crystals were also grown by same method. Crystallinity and optical distortion of TSMG YAG crystals were investigated.