摘要
以掺杂4mol%Hf4+的LiNbO3:Fe:Hf系列晶体([Li]/[Nb]比变化)为研究对象,研究了系列晶体的可见吸收光谱,在632.8nm的写入光下晶体的衍射效率、灵敏度和抗光散射能力在不同[Li]/[Nb]下的变化规律.研究发现Hf4+的浓度达到阈值浓度后,随着[Li]/[Nb]比的增大,晶体的可见吸收边会发生红移,而且晶格中[Fe2+]/[Fe3+]也会增加,这就导致随着[Li]/[Nb]比的增加,样品的衍射效率逐渐减小,写入时间缩短,灵敏度增大.同时,在晶体中,随着[Li]/[Nb]的增大,陷阱中心Fe2Li+数量增大会使得晶体抗光散射能力减弱.
Holographic storage properties and Ultraviolet-Visible absorption spectra of LiNbO3:Fe:Hf crystals adoped with Hf(4 mol%)are measured and analysised.Ultraviolet-Visible absorption edges obviously shift to long waveleng.The ratio of [Fe2+]/[Fe3+] increases with the increasing of [Li]/[Nb],which results in the deceasing of diffraction efficiency,and improving response speed and sensitivity.Moreover,the ability of light scattering resistance decreased with the increasing of [Li]/[Nb].It is contributed to the change of Fe2+Li concentration in crystals.
出处
《光子学报》
EI
CAS
CSCD
北大核心
2010年第7期1253-1256,共4页
Acta Photonica Sinica
基金
黑龙江省自然科学基金(A2007-07)资助
关键词
铪铁铌酸锂
阈值浓度
锂铌比变化
LiNbO3:Fe:Hf
Threshold concentration
Concentration of [Li]/[Nb] variation