【摘要】 使用本文介绍的生长装置已成功地生长出直径大于40mm的Nd:YAG激光晶体。在工艺上采用了大空腔保温罩、低拉速、稳定而缓慢的等径控温程序和恰当的收尾拉料操作,这是获得完整透明大尺寸Nd:YAG晶体的关键。更多还原

【Abstract】 Large Nd: YAG crystals of diameters larger than 40 mm have been succe-ssfuly grown by using the apparatus shown in this paper. In order to prevent crystalcracking, a special insulation cover was used in this apparatus, which could provide ahomogeneous temperature environment, serve for an after heater to reduce the effectof thermal shocking on crystals caused by the abrupt temperature changes, and minimizethe contamination of melts as well. It has been noted that the proper choices of the dia-meter ratio for crucible and melts and of the growth parameters, such as the pullingrate and rotating speed, are of vital importance for the growth of large crystals, beca-use tha large temperature fluctuations in the melt and changes of growth interface oftenhappen and cause serious defects in the growing crystals. Another important problemin the growth of large crystals is to prevent the deformation of crucibles, because inthis case the large crucible loaded with much raw materials is apt to deform in the longgrowth period, leading to the destruction of the stable thermal field, which is a keyfactor in the case of heating by induction. We have successfuly solved this problem byusing welded Ir crucibles with regular shape, smooth surface and homogeneous wallthickness and by taking special measures at the end of pulling。更多还原