【摘要】 我们从紫外到红外范围测量了掺入MgO和ZnO的LiNbO3 单晶的光学透射系数。计算了与波长有关的光学吸收系数α和它的根α1/2 (也相应得到了α对hν和α1/2 对hν的曲线图 ) ,并对吸收边的性质进行了分析。计算了该晶体的直接跃迁能隙Eg、间接跃迁能隙E′g 和参与间接跃迁的声子能量 ,讨论了杂质Mg和Zn对光学吸收边性质的影响。我们发现 ,双掺杂MgO和ZnO的样品的间接跃迁能隙E′g 较纯LiNbO3 晶体的间接跃迁能隙E′g 为小 ,从而导致了该样品的间接跃迁吸收边出现紫移更多还原

【Abstract】 The optical transmittance of LiNbO 3 single crystal double doped with MgO and ZnO was measured from the ultraviolet to the visible range.The wavelength dependence of the absorption coefficient α and its root α 1/2 (α versus hν and α 1/2 versus hν ,respectively)were calculated and the characteristics of the absorption edge were discussed.The energy gaps E g and E′ g of the crystals which correspond to the direct transition and the indirect transition,respectively,and the energy of phonons taking part in the indirect transition were calculated.The effects of dopants Mg and Zn on the optical absorption properties were discussed.It was found that the energy E′ g of our sample which was double doped with MgO and ZnO was smaller than that of congruent LN,causing the indirect tran aitionsabsorption edge to move towards the infrared.更多还原