L1_0-FePt为基底的纳米薄膜的磁性

Research on Magnetic Property of Nanocrystalline Films on L1_0-FePt

用L1_0相FePt作下底层,分别研究FePt(30nm,Ta)单层、L10-FePt(30nm,Ta)/A1-FePt(30nm)双层及L10-FePt(30nm,Ta)/MgO(10nm)/A1-FePt(30nm)三层薄膜的磁性,Ta=500℃。结果表明,经500℃热处理后的单层FePt磁化易轴沿垂直膜面方向,曲线矩形度较好;双层薄膜磁化曲线出现双肩现象,说明软硬磁层界面处产生强烈的交换耦合作用,软磁带动硬磁转,降低了硬磁层的矫顽力。三层膜的磁矩反转机理同双层膜一致,但中间层MgO的加入使得交换耦合作用减弱,矫顽力明显增大,软硬磁间接接触,减弱了记录噪音。

Using L10 phase FePt as the bottom layer, we studied the magnetic properties of FePt （30nm/Ta ） mono-layer film, L10 - FePt（30nm,71 ）M1-FePt（30nm） double-layer film and Ii1『FePt（30nm,Ta ）/MgO（10nm）M1-FePt（30nm） three-leyer thin film, 71 =500℃. The results show that after heat treatment at 500℃,the easy axis of single layer FePt magnetization is better in the direction of perpen-dicular film surface. The phenomenon of double shoulders in the magnetization curve of the double layer film shows that there is strong exchange coupling at the interface of the soft and hard magnetic layer, and the hard magnetic rotation is driven by the soft magnetic field, which reduces the coercivity of the hard magnetosphere. The magnetic moment reversal mechanism of the three-layer film is the same as that of the bilayer film, but the exchange coupling is weakened with the addition of MgO in the middle layer, the coercivity is obviously increased, and the soft and hard magnetic indirect contact weakens the recording noise.