講演情報
[20a-A602-4]Absorption Enhancement of WS2 with All-dielectric Metasurface Based on Mie Resonance and Degenerate Critical Coupling
〇(D)Dingwei Chen1, Junichi Takahara1,2 (1.Grad. School of Eng., Osaka Univ., 2.Photonics Center, Grad. School of Eng., Osaka Univ.)
キーワード：
metasurface、2D material、Mie resonators
Atomically thin Two-dimensional (2D) transition-metal dichalcogenides (TMDCs), such as WS2, have emerged over the past few years for their unique optical and transport features in optoelectronic and photonic applications. Nevertheless, their ultrathin thickness results in weak optical absorption. To accomplish strong light absorption, a dielectric-based metasurface based on Mie resonance and degenerate critical coupling can realize superimposed modes enhancement effects on WS2.Here, we achieve a huge absorption increase of WS2 as large as 0.73 with an all-dielectric metasurface, when peaks of electric and magnetic dipole (ED and MD) modes of metasurface overlaps in the wavelength near the peak related to excitonic transitions in monolayer WS2.This architecture could be used in the future as a highly efficient tunable single-color photodetector. Moreover, the suggested dielectric metasurface holds promise for semiconductor 2D materials in visible wavelength.