摘要
基于磁探针的边带-频率调制机理,建立了高频场磁力显微镜方法(high frequency field magnetic force microscopy method,HFF-MFM),实现了对高频磁场的动态观测。首先建立了MFM探针的力学、磁学模型,依据MFM探针的频谱测量结果,系统研究了MFM探针的边带-频率调制机理;其次,利用高频信号处理模块对探针的调制信号进行解调、提取,理论分析结合实验设计,完成了对高频磁场的直接测量。实现对纳米结构中1MHz以上磁场的直接测量。该方面的工作是MFM研究领域的一个重要进展,为进一步发展纳米尺度磁畴结构的相关精密测量技术奠定了基础。
A high frequency field magnetic force microscopy(HFF-MFM) method was developed based on the side-band frequency modulation of the cantilever resonance, to precisely observe the spin based magnetic fine structures with the modulation frequency up to MHz. In this work, according to the theoretical analysis and experimental design, alternating magnetic field variations from the magnetic writing heads have been demonstrated by HFF-MFM. The magnetic domain variations, as well as the magnetization rotations, were analyzed by HFF-MFM. The present method is an important progress in the area of MFM, and sheds light on the development for precision measurement of magnetic materials with ultra-high resolution.
引文
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