【摘要】 采用提拉法,从Li/Nb变化（0.94,1.05,1.20,1.38）的熔体中生长出Mg:Sc:Fe:LiNbO₃晶体。Li/Nb=1.05的晶体OH^-振动吸收峰在3504cm^-1处出现的主吸收峰,且在3466cm^-1、3481m^-1处有两附加峰。Li/Nb=1.38的晶体OH^-振动吸收峰在3535 cm^-1处出现附加吸收峰。红外光谱结果表示Li/Nb=1.05的晶体是近化学剂量比的,且Sc掺质优先于Mg掺质达到阈值浓度。采用透射光斑畸变法测得Mg:Sc:Fe:LiNbO₃晶体（Li/Nb=1.05）的抗光损伤能力为2.0×10⁴W/cm²,比Fe:LiNbO₃提高了三个数量级。采用波长为632.8nm的He—Ne激光器作为光源,通过二波耦合方法测试晶体全息存储性能。实验结果表明:随着Li/Nb的增加,晶体的写入时间缩短,晶体的衍射效率降低,光折变灵敏度增加,动态范围减少。在一系列晶体中,Mg:Sc:Fe:LiNbO₃晶体（Li/Nb=1.05）更加适合作为全息存储介质。更多还原

【Abstract】 Mg:Sc:Fe:LiNbO₃ crystals were grown by Czochralski method from various ratios of Li/Nb= 0.94,1.05,1.20 and 1.38 in melt.The IR spectra were measured in order to investigate their defect structures,the OH^-absorption peak of the crystals with Li/Nb=1.05 was 3466cm^-1,3481cm^-1, 3504cm^-1,while the OH^-absorption peak of the crystals with Li/Nb=1.38 was 3504cm^-1, 3535 cm^-1.The results indicated that the Sc concentration reaches the threshold priority.The optical damage resistance was characterized by the transmitted beam pattern distortion method.The threshold intensity of the crystals with Li/Nb=1.05 is 2.0×10⁴W/cm²,three orders of magnitude higher than that of Fe:LiNbO₃.The photorefractive properties of Mg:Sc:Fe:LiNbO₃ crystals were measured with He-Ne laser at the wavelength of 632.8nm by two wave coupling method.As the Li/Nb ratio increased,the diffraction efficiency and dynamic range of crystals decrease,the write time and the erasure time decrease, and the photorefractive sensitivity increase.It has been found that,the optimal Li/Nb ratios is 1.05 among this crystal series.The effect of Li/Nb ratios on the holographic storage properties of Mg:Sc:Fe: LiNbO₃ crystals is discussed.更多还原