Fabrication and design of an integrable subwavelength ultrabroadband dielectric mirror

Abstract

We have designed and fabricated a subwavelength grating (SWG) broadband mirror whose performance depends on key factors, including SWG period, duty cycle, and angle of incident light. The fabricated SWGs exhibit high reflectivity (⩾96%), when the grating periods are varied from 650to750nm and duty cycles are varied from 55% to 65%. The bandwidth and reflectivity of these mirrors are remarkably robust to variations in design and fabrication. The SWGs can be designed as broadband mirrors from microwave to visible wavelengths.