Experimental Evidence of Giant Chiral Magnetic Effect in Weyl Semimetals

Researchers at Nanjing University have reported the discovery of a giant chiral magnetic effect in type-II Weyl semimetals, a breakthrough that provides evidence of the chiral-magnetic/chiral-battery effect in these materials. This phenomenon is attributed to the chirality of Weyl fermions, which possess a longer coherent time than the Drude transport relaxation time. The research team, led by Yan-Feng Chen, observed the effect under specific conditions, including a misalignment angle between magnetic and electric fields smaller than 20 degrees, temperatures below 40 K, and externally applied electrical currents less than 50 mA.

Key Takeaways:

The chiral magnetic effect is a quantum phenomenon arising from the breaking of chiral symmetry in relativistic Weyl fermions due to quantum fluctuations under parallel electric and magnetic fields.
The research team observed a giant chiral magnetic effect in type-II Weyl semimetals, evidenced by negative resistance and corresponding voltage-current curves located in the second-fourth quadrant.
The effect occurs under specific conditions: a misalignment angle between B and E is smaller than 20 degrees, the temperature is below 40 K, the externally applied electrical current is less than 50 mA, and the magnetic field is larger than 3 T.
The phenomenon is attributed to the chirality of Weyl fermions possessing a two-order longer coherent time than the Drude transport relaxation time.
The research provides evidence of the giant chiral-magnetic/chiral-battery effect in Weyl semimetals.
The study has been peer-reviewed and published in Applied Physics Reviews.
The research team included Yan-Feng Chen, Yang-Yang Lv, Yong Zhang, Cao Lin, Bin Pang, Shu-Hua Yao, Jian Zhou, Xiao Li, Qi-Xun Wen, Su-Tao Sun, and Y. B. Chen.

Statistics:

The misalignment angle between B and E is smaller than 20 degrees.
The temperature required for the effect is below 40 K.
The externally applied electrical current must be less than 50 mA.
The magnetic field required for the effect is larger than 3 T.
The phenomenon is observed in type-II Weyl semimetals, specifically in WP2+delta crystals.
The research was supported by the National Natural Science Foundation of China (NSFC), three times.

Sources:

Medical Devices & Surgical Technology Week. NewsRx. November 2, 2025; p 394.
Applied Physics Reviews, 2025;12(3).
Aip Publishing, 1305 Walt Whitman Rd, Ste 300, Melville, NY 11747-4501, USA. (American Institute of Physics - www.aip.org/; Applied Physics Reviews - apr.aip.org/)