三方晶系的非线性磁光克尔谱及其表面磁化强度取向的效应

本文计算了三方结构不同表面和不同磁化强度取向下的χ⁽²⁾、SHG、MSHG及非线性克尔旋转角Φ_k,a⁽²⁾.结果表明,SHG和Φ_k,a⁽²⁾值非常灵敏地依赖于薄膜的表面及磁化强度的取向;三方结构的SHG、Φ_k,a⁽²⁾与fcc、bcc和hcp结构的相比有很大的差异,这表明结构对非线性磁光效应有重要的影响;当M//X、Y轴时,MSHG信号很明显,这表明可通过A值的测量来研究磁性薄膜表面的磁畴结构以及取向.

NONLINEAR MAGNETO-OPTICAL KERR SPECTROSCOPY AND EFFECT OF DIRECTION OF MAGNETIZATION ON SURFACE FOR THE TRIGONAL STRUCTURE

χ⁽²⁾,second-harmonic generation (SHG),magnetically induced second-harmonic generation (MSHG) and nonlinear magneto-optical Kerr rotation angle Φ_k,a⁽²⁾ for trigonal crystal structure have been derived.The calculated results reveal as follows:SHG and Φ_k,a⁽²⁾depend sensitively on surfaces and directions of magnetization of thin magnetic films;SHG and Φ_k,a⁽²⁾of trigonal crystal structure are different from ones of fcc,bcc and hcp structures,which means structure of crystal has an important influence on nonlinear magneto-optical effect;As M//X、Y,the values of MSHG are obvious,which means that by measuring the value of MSHG(A),the structure and direction of magnetic domain can bestudied.