High Q Factor Fano Resonances on Dielectric Metasurfaces with Si and Nitride Units

In this paper, an all-dielectric metasurface based on asymmetry of permittivity is designed with high quality factor. The periodic cell of this metasurface consists of two rectangular resonant rings. The metasurface is simulated by Finite Difference Time Domain method and the results show that the transmission spectrum has four Fano resonance peaks in the near-infrared band, and two of the resonance modes are based on quasi-BIC modes, whose quality factors are calculated to be 9651 and 110902, respectively. This study opens new possibilities of metasurface design and device performance.