用纵向磁光克尔效应观察Co/Cu/Co三层膜正交方向磁矩随磁场的翻转过程

Reversal process of magnetization of a Co/Cu/Co trilayer observed by longitudinal MOKE technique

运用光弹调制器和锁向放大器作为主要的光电子仪器,搭建磁光克尔效应实验系统,将平行和垂直磁场应用于纵向磁光克尔(Kerr)效应,用来分析薄膜正交方向磁矩随磁场翻转的情况.应用此方法,研究了在不同衬底上用磁控溅射方法制备的Co(2.7nm)/Cu(2nm)/Co(2.7nm)三层膜的磁性及磁矩翻转,探索其耦合机理.衬底与间隔层Cu层表面结构的差异,诱导了底层Co与表面层Co结构的差异,导致底层和表面层Co膜的矫顽力不同,从而实现了两铁磁层的磁矩翻转不一致.

A set of experimental system of magneto-optic Kerr effect was set up mainly by using photo-elastic modulator and lock-in amplifier. The system was used to measure the magnetic properties of magnetic materials, especially for magnetic thin films. The longitudinal magneto-optical Kerr effect was used to investigate the magnetic properties and magnetic reversal. Transverse and longitudinal magnetic fields were applied in the plane of the samples in order to measure two perpendicular magnetization components in-plane. Co/Cu/Co sandwiches deposited on different substrates were prepared by high vacuum magnetron sputtering. From Kerr loops, the different of structure between buffer and Cu layer induced the difference of structure between Co down-layer and Co up-layer, which made the coercive force difference and magnetization reversal.