Open AccessTerahertz bound state in the continuum in dielectric membrane metasurfaces
Author(s) -
zuolong li,
Jianqiang Gu,
Quanlong Yang,
Xueqian Zhang,
Jiaguang Han,
Quan Xu,
Luyao Wang,
Xu Yi,
Ivan I. Kravchenko,
tianyu shao
Publication year - 2022
Publication title -
new journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.584
H-Index - 190
ISSN - 1367-2630
DOI - 10.1088/1367-2630/ac66f8
Subject(s) - physics , terahertz radiation , multipole expansion , harmonics , superposition principle , resonator , optics , dielectric , bound state , electromagnetic radiation , photonics , optoelectronics , quantum mechanics , voltage
Mie-resonant metasurfaces composed of subwavelength dielectric resonators enable an efficient route for electromagnetic wave manipulation. Among these manipulations, a localized mode with a high-quality factor coexisting with a continuous spectrum of radiating waves termed bound state in the continuum (BIC) can arouse many exotic applications in photonics. Here, we demonstrate the terahertz BIC in a dielectric membrane metasurface and analyze its resonant nature based on Mie-resonant multipoles and vector spherical harmonics. The intrinsic splitting of the resonances under oblique incidence is also explored, in which the conversion of multipole radiation patterns versus the oblique angle will drive the resonances from BIC to leaky modes or vice versa. Both Γ and off−Γ point BICs could be identified as the superposition cancellation of vector spherical harmonics for both p-wave and s-wave. Our research not only provides a novel perspective for exploring the essence of BIC metasurfaces in the terahertz regime, but also points new opportunities for achieving terahertz BIC metasurfaces with ultra-high quality factors.