Design of High-Index-Contrast Grating as Quarter-Wave Plates

This paper focuses on the quarter-wave plate design based on subwavelength high-index-contrast grating (HCG). The relationship among the equivalent refractive index of the HCG, the duty cycle of grating and the incident wavelength was obtained with the theory of effective medium and rigorous coupled wave analysis. By selecting the parameters and using the iterative algorithm proposed in this paper, quarter-wave plates with excellent performance can be obtained.