紫外低吸收GdAl3（BO3）4晶体生长和266nm激光输出研究

项目名称： 紫外低吸收GdAl3（BO3）4晶体生长和266nm激光输出研究

项目编号： No.51202259

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 无机非金属材料学科

项目作者： 岳银超

作者单位： 中国科学院理化技术研究所

项目金额： 25万元

中文摘要： GdAl3(BO3)4(GAB)晶体自1960年代被发现以来，研究集中在稀土掺杂GAB晶体生长和其在激光自倍频方面的应用。由于通常采用钼酸盐助熔剂生长的GAB晶体紫外截止边在300nm左右，到目前为止，GAB作为应用于紫外短波段非线性光学晶体研究很少。近期，我们探索出一种"金属氧化物-B2O3-氟化物"助熔剂体系，生长的GAB晶体紫外截至边在175nm，且较同结构类型YAl3(BO3)4更易生长出大尺寸晶体。GAB晶体的粉末倍频效应约为3.5倍KDP且能够实现相位匹配，GAB晶体不潮解、硬度大，抗激光损伤阈值约为11.31GW/cm2，使其在紫外短波段应用成为可能。本研究包括紫外低吸收GAB晶体的助熔剂体系探索与优化、单晶生长，线性与非线性光学性能表征等，将首次实现GAB晶体的Nd:YAG(1064nm)激光266nm输出。GAB晶体可能成为有应用前景的四倍频非线性光学晶体。

中文关键词： GAB；助熔剂；透过率；双折射率；四倍频

英文摘要： GdAl3(BO3)4 (GAB) crystal has been discovered since the 1960s, which was mainly studied as a self-frequency-doubling material for laser application. So far it is rarely reported that GAB is studied as a nonlinear crystal in the ultraviolet applications,because the UV cut-off edge of GAB crystal grown from molybdate flux is about 300nm. Recently, we explored a new flux system(Metal oxides-B2O3- Fluoride). The UV cut-off edge of GAB crystal grown from the new flux is about 175nm and GAB large size crystal growth is easier than YAl3(BO3)4 base on the new flux system. The powder SHG of GAB is about 3.5 times of KDP and laser damage threshold is 11.31GW/cm2. GAB grown crystal exhibits good chemical stability, free of moisture and hygroscopy, and excellent mechanical properties. Therefore, GAB is able to use as a nonlinear optical crystal in the ultraviolet. This study includes exploration and optimization of flux system for low UV absorption GAB growth, crystal growth process, and linear and nonlinear optical characterization. It is the first time to achieve fourth harmonic (266nm) laser output through using GAB crystal. As a result, GAB crystal is possible to use as a new alternative four-frequency-doubling crystal material in the Nd: YAG (1064nm) laser.

英文关键词： GAB；flux；transmittance；birefringence；FoHG