[8a-A22-1~8] 4.1 Plasmonics and Nanophotonics

10:00 AM - 10:15 AM JST(1:00 AM - 1:15 AM UTC)English Presentation

[8a-A22-4] Embedded Quasi-BIC Metasurfaces with Planar Surface for Nonlinear Optical Characterization of 2D Materials

〇Wei-Ting Chiang¹, Zi-Juan Chen¹, Yang-Chun Lee¹ (1.Natl. Taiwan Univ. Sci. Technol.)

Keywords:

embedded metasurface,quasi-BIC,Second Harmonic Generation

2D materials have attracted great interest in photonics due to their unique properties. Second Harmonic Generation (SHG), a non-destructive probe sensitive to crystal symmetry, holds strong potential for 2D material characterization. However, their atomic-scale thickness yields weak SHG signals. Conventional metasurfaces exploiting quasi-bound states in the continuum (quasi-BIC) amplify these signals, yet their non-planar interfaces leave materials partially suspended, inducing heterogeneity and compromising accuracy. Here, we propose an embedded metasurface where the periodic grating driving the quasi-BIC resonance is concealed beneath a high-refractive-index waveguide layer. This flat interface achieves significant SHG enhancement while preserving the material's pristine state. Our approach eliminates environmental interference of open structures, offering a reliable, non-destructive platform for high-precision optical characterization of 2D materials.