Spotlights

[Research News] From Noise to Power: A Symmetric Ratchet Motor Discovery

From random chaotic vibrations to useful motion—toward new energy-harvesting technologies

Researchers, including Miku Hatatani, a Ph.D. student in the Department of Chemical Engineering and Materials Science, have developed the world’s first symmetric ratchet motor in which a perfectly circular disk spins in one direction when placed on vibrating particles, inspired by molecular motors in biological systems. While conventional rachets rely on asymmetry, this motor emerges from spontaneous symmetry breaking. This discovery highlights a new principle in physics of extracting order from noise, setting the stage for innovative energy-harvesting devices that work on ambient vibrations.


Reference
Hatatani, M., Oguni,J., Yamamoto, D., & Shioi, A., Emergence of a ratchet motor by spontaneous symmetry breaking, Chaos 35,（８）, 083102 (2025).
https://doi.org/10.1063/5.0271467

For more details, please see the website of Organization for Research Initiatives and Development, Doshisha University. 

https://research.doshisha.ac.jp/news/news-detail-80/

This achievement has also been featured in the “EurekAlert!.”
News Release 11-Sep-2025,

https://www.eurekalert.org/news-releases/1097937

Title: Mechanism of Spontaneous Symmetry Breaking in a Symmetric Ratchet Motor
Caption: In the initial setup, the particles are evenly distributed. But when the disc is placed on the particle bed and subjected to vibration, it spontaneously begins to spin in one direction, demonstrating self-organization arising from breaking of symmetry.
Image credit: Ms. Miku Hatatani from Doshisha University, Japan
Image license: Original content
Usage restrictions: Cannot be used without permission.