垂直磁记录薄膜交换耦合作用及开关场分布的测量

采用Lakeshore7407型振动样品磁强计，以Co-Pt垂直磁记录薄膜为例，详细介绍了垂直薄膜等温剩磁(isothermalremanentmagnetization，IRM)曲线、直流退磁剩磁(directcurrentdemagnetizationremanence，DCD)曲线的测量方法和退磁因子的计算方法，并给出根据退磁场修正后的IRM和DCD曲线计算垂直磁记录薄膜曲线和开关场分布(SFD)的方法.最后详细讨论了薄膜的微观组织和易磁化轴取向分布对退磁场、交换耦合作用和SFD的影响.结果表明:退磁场的存在使得直接测量得到的晶粒间交换耦合作用偏小，开关场分布宽化；影响晶粒间交换耦合作用的内在原因是介质的微观组织和易磁化轴的取向分布.

Determination of Exchange Coupling and Switching Field Distribution for Perpendicular Magnetic Recording Media

The magnetic properties of the Co-Pt perpendicular magnetic recording films were characterized with a vibrating sample magneto-meter. The measurement techniques of the isothermal remanent magnetization (IRM) and direct current demagnetization remanence(DCD) and demagnetization factor calculation were presented in detail for the perpendicular recording media. In addition, the calculation methods of ΔM and switching field distribution(SFD) from the corrected demagnetization IRM as well as DCD curve were introduced. Finally, the relationship was discussed in detail among the intergranular exchange coupling, SFD, demagnetization, microstructure, and the easy magnetization axis orientation distribution of the Co-Pt thin films. The results show that the intrinsic constant of intergranular exchange coupling that mainly depends on the microstructure and easy magnetization axis orientation distribution of recording media is decreased with the demagnetization, while the SFD will be broaden, and the easy magnetization axis orientation distribution is an influencing factor for SFD.