School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States.
Nano Lett. 2021 Jun 23;21(12):4966-4972. doi: 10.1021/acs.nanolett.1c00704. Epub 2021 Jun 8.
Magnetic microscopy that combines nanoscale spatial resolution with picosecond scale temporal resolution uniquely enables direct observation of the spatiotemporal magnetic phenomena that are relevant to future high-speed, high-density magnetic storage and logic technologies. Magnetic microscopes that combine these metrics has been limited to facility-level instruments. To address this gap in lab-accessible spatiotemporal imaging, we develop a time-resolved near-field magnetic microscope based on magnetothermal interactions. We demonstrate both magnetization and current density imaging modalities, each with spatial resolution that far surpasses the optical diffraction limit. In addition, we study the near-field and time-resolved characteristics of our signal and find that our instrument possesses a spatial resolution on the scale of 100 nm and a temporal resolution below 100 ps. Our results demonstrate an accessible and comparatively low-cost approach to nanoscale spatiotemporal magnetic microscopy in a table-top form to aid the science and technology of dynamic magnetic devices with complex spin textures.
磁性显微镜将纳米级空间分辨率与皮秒级时间分辨率相结合，能够独特地直接观察与未来高速、高密度磁存储和逻辑技术相关的时空间磁现象。将这些指标结合起来的磁性显微镜一直局限于设施级仪器。为了解决实验室可访问的时空间成像中的这一差距，我们开发了一种基于磁热相互作用的时间分辨近场磁性显微镜。我们演示了磁化和电流密度成像模式，每个模式的空间分辨率都远远超过了光学衍射极限。此外，我们研究了我们信号的近场和时间分辨特性，发现我们的仪器具有 100nm 量级的空间分辨率和低于 100ps 的时间分辨率。我们的结果展示了一种可访问且相对低成本的方法，可以在台式设备中实现纳米级时空间磁性显微镜，以帮助具有复杂自旋结构的动态磁性器件的科学和技术发展。
