LiNbO_3:Ni^(2+)晶体的精细光谱和扬特勒效应

Spectral Fine Structure and Jahn-Teller Effect of LiNbO_3\:Ni^(2+) Crystals

应用晶体场理论和不可约张量算符方法构造了3d8态离子在C3v对称晶场中包含自旋轨道相互作用、自旋自旋相互作用、自旋轨道相互作用和其它轨道其它轨道相互作用4种微观磁效应的45阶可完全对角化的能量哈密顿矩阵。研究表明LiNbO3:Ni2+晶体中存在扬特勒(Jahn-Teller)效应;自旋轨道相互作用对晶体光谱和零场分裂参量的贡献是最主要的,考虑其他3种微观磁效应后计算值更加接近实验值。

Applying crystal field theory and irreducible representation method,the completely diagonalized Hamiltonian matrices of 3d8 ion configurations in the trigonal symmetry sites have been established,which include four kinds of microscopic magnetic interactions： spin-orbit interaction,spin-spin interaction,spin-other-orbit interaction and orbit-orbit interaction.Based on the matries,spectral fine structure and zero-field splitting parameters of LiNbO3／：Ni2＋ crystall are calculated.Jahn-Teller effect,and effects of four microscopic magnetic interoctions on crystal spectral and zero-field splitting parameter are investigated.The results show that Jahn-Teller effect exists in this crystal and spin-orbit interaction makes uppermost contribution to energy level and zero-field splitting parameters while calculated values will be closer to the experimental values when the other three interactions are taken into account.