hcp结构的Co磁性膜表面和界面的非线性克尔旋转及SHG的研究

本文基于对称性理论、磁性表面的菲涅耳反射和折射定律,研究了hcp(密排六方体)Co结构的χ⁽²⁾、SHG(二次谐波振荡)信号强度和非线性磁光克尔旋转角Φ_k,α⁽²⁾与入射角、偏振角及光子能量的关系.结果表明,Φ_k,α⁽²⁾比线性克尔角有巨大的增强;当接近垂直入射时,Φ_k,α⁽²⁾接近90°;Φ_k,α⁽²⁾灵敏地依赖于M的影响,从而可以通过Φ_k,α⁽²⁾来决定薄膜中的晶轴方向和磁化强度的取向.

THE NONLINEAR MAGNETIC-OPTICAL KERR ROTATION AND SHG AT SURFACES AND INTERFACE IN hcp Co THIN FILM

Based on the symmetric theory,the laws of Fresnel reflection and refraction and electronic theory at surface,it is studied nonlinear magneto-optics Kerr angle and SHG intensity as a function of the angle of incidence θ,the polarization angle φ and the photon energy The calculated results reveal that,comparing the linear magneto-optical Kerr algle,Φ_k,α⁽²⁾ has a giant enhancements:As θ→0°,Φ_k,α⁽²⁾→90°;Φ_k,α⁽²⁾ value depends sensitively to the direction of magnetization at surfaces and interfaces Therefore,the nonlinear magneto-optical Kerr effect may become a sensitive tool to determin the magnetization and easy axes at surfaces and interfaces.