【摘要】 在同成分铌酸锂(LiNbO3,LN)晶体中,掺入的摩尔分数分别为0,1%,3%,6%MgO,掺入0.1%(质量分数,下同)CuO和0.05%CeO2,采用提拉法生长了优质的Mg:Ce:Cu:LN晶体,对生长后的晶体极化后分别进行了氧化和还原处理。测定了Mg:Ce:Cu:LN晶体的紫外-可见光吸收光谱和光折变性能。结果表明:与未经氧化和还原处理的晶体相比,在掺MgO量为1%和3%时,经氧化处理的晶体的吸收边发生了紫移,经还原处理的晶体的吸收边发生了红移;而在掺MgO量为6%时,氧化处理后晶体的吸收边紫移趋势不明显。氧化处理后晶体的抗光损伤能力R减弱,而还原处理后晶体的R增强;而当掺入MgO为6%时,Mg:Ce:Cu:LN晶体的R最大,Mg:Ce:Cu:LN晶体的R比Ce:Cu:LN晶体高2个数量级。结合铌酸锂晶体的锂空位缺陷模型解释了有关实验结果。更多还原

【Abstract】 Mg:Ce:Cu:LiNbO3(Mg:Ce:Cu:LN) crystals doped with 0,1%(in mole,the same below),3%,6%MgO,and 0.10%(in mass,the same below) CeO2 and 0.05%CuO respectively were grown by the Czochralski method from congruent LN melting.After polarization,the crystals were oxidized and reduced.The ultraviolet-visible absorption spectra and the photorefractive properties of the three kinds of Mg:Ce:Cu:LN crystals were measured.The experimental results that compared to grown crystals,when doped-Mg content of 1% and 3%,the absorption edge of oxidized crystals is shifted to the violet band and that of reduced crystals is shifted to the infrared band,and at doped-Mg content of 6%,the absorption edge of oxidized crystals exhibited a no clear violet shift.The opti-cal damage resistance ability R of oxidized crystals decrease,and R of reduced crystals increase and R of reduced crystals doped with 6%Mg achieve maximum.The R of Mg:Ce:Cu:LN crystal is increased about 2 order of magnitude compared to that of Ce:Cu:LN crystal.Some related experimental results were explained based on Li-vacancy defect model.更多还原