Subwavelength Multilayer Binary Grating Design for Implementing Photonic Crystals

Abstract

Subwavelength multilayer binary gratings (SMBG) can be seen as a 2-D periodic structures (see Fig.1a) with two periodic directions along the grating vector and the multilayer cascading direction. Such structures combine strong form- birefringence1,2 of the subwavelength grating with high reflectivity due the multilayer structure allowing us to design polarization sensitive microdevices, such as polarization selective mirror and polarizing beam splitter. Recently3 we introduce a new polarizing beam splitter (PBS) microdevice design built of SMBGs. Not only this novel design increases the angular and spectral range of the PBS microdevice in comparison to conventional PBS designs, but most importantly, our microdevice can operate with normally incident light, acting as a high-efficiency polarization-selective mirror. Microdevice with such features are critical for microlaser designs. Since the SMBG is a 2-D periodic structure, it can also be used to design a 2-D photonic crystal. In this manuscript, we summarize the design, modeling, and characterization of the SMBG structure designed to implement polarization sensitive microdevice, and also introduce and discuss a 2-D photonic crystal design based on SMBG.