Reflection performance research of grating with polarization independence based on a sandwiched structure

Abstract

The novel reflective grating was studied under Littrow incidence as one sort of high-efficiency optical element. A covering layer and a dielectric layer are employed in this structure to achieve higher efficiency and wider bandwidth. For the given wavelength of 1550 nm, by using two-beam-interference theory of modal method, duty cycle and period of grating can be calculated, where the physical essence of high efficiency in the first-order is well explained by the modal method. The other grating parameters are optimized by using rigorous coupled-wave analysis. The optimized grating has an appropriate aspect ratio and shows that diffraction efficiencies of TE and TM polarizations in the first-order are greater than 97%. Compared with the reported surface-relief high-efficiency grating, the diffraction efficiencies of the proposed grating for TE and TM polarizations can be greatly improved.

Two-dimensional grating metasurface for communication band under Littrow mounting

“…As one of the essential optical components, grating devices [5,6] are widely used in integrated optical communication systems [7,8] because of their compact structure, simple preparation process and convenience of integration. A wide range of optoelectronic components and modules have been designed based on gratings, including couplers [9], filters [10,11], beam splitters [12,13] and sensors [14,15], which can be used to form and expand * Author to whom any correspondence should be addressed. more complex photonic integrated circuits [16].…”