Gd掺杂FeCo薄膜的磁性和磁化反转机制研究

The study of magnetic properties and magnetization reversal mechanism of Gd doped FeCo thin films

采用直流磁控共溅射方法制备了Gd掺杂FeCo磁性薄膜。XRD测量结果表明,随着溅射功率的增加其结构发生从纳米晶到晶态的转变。研究了磁性随温度的变化规律,结果表明,在温度降到120K左右,晶态样品存在由面内单轴各向异性向具有垂直各向异性转变的自旋重取向(SRT)现象。而纳米晶态样品在温度降到能够达到的最低温度100K时仍然没有出现SRT。对纳米晶薄膜矫顽力的角度依赖性研究表明,当外磁场靠近易轴附近时反磁化机制为畴壁成核或者畴壁钉扎,当磁场靠近难轴时的反磁化机制为一致转动。

Gd doped magnetic FeCo thin films were fabricated by DC magnetron co-sputtering at ambient condi-tion.The structure transition from nano-crystalline structure to crystalline structure were characterized by XRD upon increasing sputtering power.A spin reorientation transition from in-plane uniaxial anisotropy to perpendic-ular anisotropy was observed as the temperature decreasing to around 120 K for crystalline sample.While the SRT was absent in the nanocrystalline sample as the temperature decrease to the lowest available temperature of 100 K.The investigation of the angular dependence of coercivity indicates that the magnetization reversal mech-anism of nanocrystalline FeCoGd film was domain-wall depinning or nucleation and coherent rotation when the applied field was close to the easy axis and hard axis,respectively.