Binary zero-order diffractive and anti-reflective optical elements in silicon for the mid-infrared

Smolik, Grégoire MaximeHerzig, Hans Peter2017-08-312017-08-312017-08-31201710.1364/OL.42.003233https://infoscience.epfl.ch/handle/20.500.14299/139928WOS:000407640000045We propose a novel method for the design of binary 2-level diffractive optical elements that provide an efficient diffractive function while reducing the reflectivity of a high-index interface. The structure can be fabricated with a single patterning step and is particularly useful for the mid-infrared spectral range. The concept is based on zero-order transmission gratings using subwavelength micro-structures. To demonstrate the concept a Dammann grating has been realized in silicon and characterized in the mid-infrared by scanning the far-field intensity distribution.Diffraction and gratingsSubwavelength structuresEffective medium theoryDiffractive opticsMetamaterialsBinary zero-order diffractive and anti-reflective optical elements in silicon for the mid-infraredtext::journal::journal article::research article