提拉法生长直径10英寸优质Yb∶YAG激光晶体

Growth of High Qualityϕ10 Inch Yb∶YAG Laser Crystal by Czochralski Method

设计制作了直径10英寸Yb∶YAG激光晶体生长热场,改进了单晶炉称重与旋转系统结构,采用感应加热熔体提拉法结合上称重自动控径技术,成功生长出了直径252 mm、等径长近260 mm的完整Yb∶YAG晶体,晶坯外观完整,无开裂。在5 mW绿光激光和20 mW He-Ne激光照射下检测,晶坯整体无散射。经检测性抛光后,晶坯选材扇区内光学均匀性较好,应力分布均匀。选择口径为152 mm×11.5 mm、长为260 mm的板条区域进行测试,透过波前畸变为0.29λ/inch@633 nm,表明晶坯具有良好的光学质量,可以选切加工宽度达到150 mm的大尺寸晶体板条元件。

The thermal field of growing Yb∶YAG laser crystal with a diameter of 10 inch has been designed and fabricated,and the structure of single crystal growth furnace has been improved.The Yb∶YAG crystal with a diameter of 252 mm and a cylinder length of nearly 260 mm has been successfully grown by induction heating Czochralski method combined with automatic diameter control system.There is no visible crack and scattering particle under the irradiation of 5 mW green laser and 20 mW He-Ne laser in the boule.The optical uniformity and stress of the boule was inspected after polishing.The results show that the available sectors of this boule have good optical uniformity and uniform stress distribution.A crystal slab with size of 152 mm×11.5 mm×260 mm can be selected in one available sector of this boule,and its transmitted wavefront distortion is 0.29λ/inch@633 nm.