A research team led by Prof. LU Qingyou from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences has made a major breakthrough by developing a magnetic force microscope (MFM) that can image air-sensitive materials without the need for surface protection coatings.

Featured on the cover of Review of Scientific Instruments, this invention highlights a significant advance in scientific instrumentation.

The study of magnetic properties in two-dimensional van der Waals materials holds great promise for applications in spintronics and high-density data storage due to their nano- and atomic-scale magnetic structures. However, air sensitivity makes it difficult to directly characterize the intrinsic magnetic properties of these materials.

In this study, the compact MFM system addresses this challenge by providing a controlled environment for imaging air-sensitive materials with precision and reliability.

"It's small," said Dr. ZHANG Yuchen, a member of the team, "and because the microscope can be disassembled, we can do the whole process in inert gas using a glovebox."

What she is referring to is a unique removable sealed chamber of the MFM probe. When sensitive samples are moved from a glovebox to a low temperature, high magnetic field environment, it can effectively protect them from air exposure.

This ensures the integrity and cleanliness of the sample surface, enabling the acquisition of high-resolution images that reveal the intrinsic magnetic structures of materials such as chromium triiodide (CrI₃).

The successful development of this glovebox-assisted MFM system marks a significant step forward in magnetic microscopy technology. "It paves the way for future advances in magnetic materials research and next-generation magnetic storage devices," said Dr. ZHANG.

The compact MFM is a unique detachable sealed chamber. (Image by ZHAO Weiwei)

Cover image of Review of Scientific Instruments (Image by ZHANG Yuchen)

Topography and MFM images of the CrI3 bulk crystal at 5 K and in fields up to 11.9 T. (Image by ZHANG Yuchen)