Abstract
Instead of a conventional fixed multilayer grating, a self-suspended subwavelength grating (SSG) which consists of a single grating layer and possesses tunable functions, is investigated by the rigorous coupled-wave method in detail. Through optimizing various parameters including the incident wavelength, the grating period, the grating thickness and the grating filling factor, we demonstrate that the silicon dioxide (SiO2) SSG owns a narrow reflectance linewidth in the case of TE polarization. For the SiO2 SSG, the reflectance peak splits into two branches when the incident light deviates from normal incidence. In addition, the reflectance property of the SiO2 SSG with unoptimized parameters is also presented for comparison, which exhibits a much larger reflectance linewidth. It is expected that the SiO2 SSG should be used as narrow bandstop optical filters for TE polarization in micro optics systems.
Acknowledgements
This work was supported by the Grant-in-Aid for Scientific Research (17068002). This work was also supported by Grant-in-Aid for Publication of Scientific Research Results (18·06375) from the Japan Society for the Promotion of Science (JSPS).