Affiliation:
1. Harbin Institute of Technology
Abstract
Metasurface supporting bound states in the continuum (BIC) provides a unique approach for the realization of intense near-field enhancement and high quality factor (Q-factor) resonance, which promote the advancement of various applications. Here we experimentally demonstrate a Friedrich–Wintgen BIC based on the mode coupling in the terahertz metasurface, which produces BIC by the coupling of the LC mode and dipole mode resonances. The transition from ideal BIC to quasi-BIC is caused by the mismatch of the coupling, and the mode decay rate during this process is analyzed by temporal coupled mode theory. The Q-factor and the electric field enhancement of the quasi-BIC resonance are significantly increased, which provides enormous potential in sensing, nonlinear optics, and topological optics.
Funder
National Natural Science Foundation of China
Youth Innovation Team of Shaanxi Universities
Key Research and Development Program of Shaanxi Province
Natural Science Foundation of Shaanxi Province
Subject
Atomic and Molecular Physics, and Optics