Wu Xiqi, Zhang Wenhao, Wang Wenting, Chen Yuhang
Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei 230027, People's Republic of China.
Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei 230027, People's Republic of China.
Nanotechnology. 2022 Aug 31;33(47). doi: 10.1088/1361-6528/ac8998.
Magnetic force microscopy (MFM) has become one of the most important instruments for characterizing magnetic materials with nanoscale spatial resolution. When analyzing magnetic particles by MFM, calibration of the magnetic tips using reference magnetic nanoparticles is a prerequisite due to similar orientation and dimension of the yielded magnetic fields. However, in such a calibration process, errors caused by extra electrostatic interactions will significantly affect the output results. In this work, we evaluate the magnetic moment and dipole radius of the MFM tip on FeOnanoparticles by considering the associated electrostatic force. The coupling of electrostatic contribution on the measured MFM phase is eliminated by combining MFM and Kelvin probe force microscopy together with theoretical modeling. Numerical simulations and experiments on nickel nanoparticles demonstrate the effectiveness of decoupling. Results show that the calibrated MFM tip can enable a more accurate analysis of micro-and-nano magnetism. In addition, a fast and easy calibration method by using bimodal MFM is discussed, in which the acquisition of multiple phase shifts at different lift heights is not required.
磁力显微镜（MFM）已成为用于以纳米级空间分辨率表征磁性材料的最重要仪器之一。在用MFM分析磁性颗粒时，由于所产生磁场的方向和尺寸相似，使用参考磁性纳米颗粒对磁探针进行校准是一个先决条件。然而，在这样的校准过程中，由额外的静电相互作用引起的误差将显著影响输出结果。在这项工作中，我们通过考虑相关的静电力来评估MFM探针在FeO纳米颗粒上的磁矩和偶极半径。通过将MFM与开尔文探针力显微镜以及理论建模相结合，消除了静电贡献对测量的MFM相位的耦合。对镍纳米颗粒的数值模拟和实验证明了解耦的有效性。结果表明，校准后的MFM探针能够对微纳磁性进行更准确的分析。此外，还讨论了一种使用双峰MFM的快速简便的校准方法，其中不需要在不同提升高度获取多个相移。
