The University of Tokyo
RIKEN
Japan Science and Technology Agency (JST)

Summary of Presentations

A research group led by Assistant Professor Hironari Isshiki, Graduate Student Nico Budai, Graduate Student Ayuko Kobayashi (at the time of the research), Graduate Student Ryota Uesugi (at the time of the research), Professor Yoshichika Otani (team leader at RIKEN), Project Associate Professor Tomoya Higo and Professor Satoru Nakatsuji at School of Science, The University of Tokyo, has successfully visualized the magnetic polarization of an antiferromagnetic Weyl semimetal using a new and simple method. Using a method developed by the group in 2023 (Fig), which applies a heat flow into a sample through a tiny needle and detects the local magneto-thermoelectric response to obtain a magnetic image, magnetic imaging was performed on a nano-wire of Mn₃Sn. The magnetic imaging of nanoscale samples, which conventional methods could not investigate, revealed the magnetic behavior of Mn₃Sn processed to a nanometer scale. Understanding the magnetic behavior of nanoscale materials is essential for the development of next-generation spintronics devices that enable ultrafast and ultra-power-efficient information communication and computation and ultra-sensitive sensing.

Figure :Schematic illustrations of magneto-thermoelectric effect (left) and new magnetic imaging method (right)
Left: The resulting voltage (V) is proportional to the cross-product of magnetic polarization and heat flux. Right: By measuring the magneto-thermoelectric signal (V) generated by injected heat flux, the direction of magnetic polarization can be investigated.

For more information, please visit the website of the Institute for Solid State Physics, The University of Tokyo.（in Japanese）

Journals

Journal name	Physical Review Letters
Title of paper	Observation of cluster magnetic octupole domains in antiferromagnetic Weyl semimetal Mn3Sn nanowire