Perovskite and Graphene-Based Meta-Devices for Effective Optical Modulation of THz Waves

Active and effective control over terahertz (THz) waves is essential for THz applications, and the incorporation of dynamic materials into metasurfaces offers opportunities to realize highly efficient THz manipulation. Here, optically controlled THz metasurface devices (meta-devices) based on either perovskite or graphene are experimentally demonstrated, each exhibiting ultra-sensitive THz modulation under extremely low external optical power. We achieve a maximum modulation depth of 237.5% in the THz transmission amplitude of a metal-perovskite hybrid meta-device when the power density is as low as 13.7483 mW/cm
²
. Moreover, a metal-graphene hybrid meta-device also shows ultra-sensitive optically induced characteristics, with a maximum modulation depth of 403.36% under the extremely low power density of 11.1846 mW/cm
²
. These devices offer a meaningful guide for the design of tunable terahertz meta-devices that will find utility in applications that require the ultra-sensitive optical modulation of terahertz waves.