Subwavelength grating devices for optical on-chip multiplexing

The multiplexing technology is an effective approach to enhance the capacity of optical communication system while numerous kinds of multiplexing devices have been proposed. Subwavelength gratings (SWGs) are periodic structures with pitches small enough to locally synthesize the refractive index. This talk provides an introduction to the basics of SWG and particularly focuses on the design strategies of some SWG based devices in multiplexing system, including polarization independent directional coupler, polarization beam splitter and wavelength multiplexer. With SWG to engineer the refractive index, birefringence and dispersion, these devices possess more design freedoms and exhibit a better performance.