News from our newspaper (Reporter Yang Fan, Correspondent Gui Yunan) Recently, the Lu Qingura Research Group of the High Magnetic Field Center of the Hefei Institute of Material Science of the Chinese Academy of Sciences successfully developed an atomic resolution scanning tunneling microscope (STM) for hybrid magnets under extreme conditions for the first time in the world. Hybrid magnets and STM have paved the way for atomic resolution imaging research. The research results were published in "Ultramicroscopy" and "Science Instrument Review".

Under the extreme environment of magnetic field, researchers have discovered many important physical phenomena. At present, the strongest steady-state magnetic field in the world is obtained through hybrid magnets. Due to the interference of strong vibration during the operation of the hybrid magnet, it can only be used to measure the macro-average effects such as transportation, magnetism, magneto-optical, etc. in the world. However, real-space atomic resolution measurement is closer to revealing the microscopic quantum origin of physical properties, and plays a decisive role in the exploration of new electronic materials and nanomaterials, new physical properties, and new theories.

In this research, based on the small-size "spider motor", Lu Qingyou’s research group proposed a new tube-shaped coarse-approximation piezoelectric motor and The integrated mechanical tandem STM lens body of the scanning imaging unit is mainly processed by sapphire insulating material with an outer diameter of only 8.8 mm. It can be directly inserted into the 32 mm room temperature magnet aperture of the hybrid magnet and vacuum sealed.

After testing, the research team successfully obtained high-quality, atom-resolved STM images of graphite under the super-strong magnetic field of 30 Tesla. This narrow-space compatible plug-in hybrid magnet STM can be easily transplanted into a liquid helium thermostat suitable for hybrid magnets to carry out super-strong magnetic field low-temperature research.

At the same time, they built a set of split STM for high-resolution imaging of biomolecules under a super-strong magnetic field. After testing, the STM still maintains atomic resolution under a super strong magnetic field of 27.5 Tesla.

Related paper information: https://doi.org/10.1063/1.5140423

https://doi.org/10.1016/j.ultramic.2020.112975

China Science News (2020-06-23 4th edition comprehensive)