[9p-C213-1~12] 3.8 Terahertz technologies

4:30 PM - 4:45 PM JST(7:30 AM - 7:45 AM UTC)

[9p-C213-10] Optically reconfigurable terahertz wavefront control using magnetic Weyl semimetal thin films

〇Naotaka Yoshikawa¹, Kohei Fujiwara², Atsushi Tsukazaki³, Ryo Shimano^1,4 (1.Dept. of Phys. Univ. of Tokyo, 2.Dept. of Chem., Rikkyo Univ., 3.QPEC & Dept. of Appl. Phys., Univ. of Tokyo, 4.Cryogenic Research Center, Univ. of Tokyo)

Keywords:

Terahertz,Metasurface,Weyl semimetal

We demonstrate optically writable terahertz (THz) wavefront control using the giant magneto-optical response of the ferromagnetic Weyl semimetal Co₃Sn₂S₂. Magnetic domain patterns created by all-optical magnetization switching serve as phase masks for THz waves, enabling control of the frequency response, phase, and intensity of diffracted THz waves. We further demonstrate selective control of higher-order diffraction components and polarization-selective THz focusing using Fresnel-zone-plate domain patterns. This work establishes a new platform for optically reconfigurable and non-volatile THz metasurfaces without electrical wiring.