Three Dimensional High Contrast Gratings based Hollow Core Waveguide for Chip Scale Integrated Optical Interconnects

Abstract

Three dimensional high contrast gratings based hollow core waveguide is a potential candidate for telecommunication systems which provides a promising platform to realize integrated optical interconnects. These have been comprehensively studied over the years due to its diverse applications in the communication systems. With advancement of technologythese days as we are doing scaling the size of devices and distance between the devices is reducing which makes interconnects more important in communication system. To maintain such high speed and small size optical interconnects are required which can play crucial role to achieve today’s high speed large bandwidth requirementsThe high reflectivity, high speed and high bandwidth of HCGs based Hollow waveguide is one of the key component for integrated chip scale optical interconnects.This can be used to guide light and transmit Tb/s data over the communication link and attracted a lot of attention for next generation communication network as well as high performance computing applications.SOI is an ideal platform for the development of passive optical interconnects like Hollow waveguide. Several key challenges exist in developing the waveguide, including fabrication difficulties, dispersion and non linearity. Usinghigh contrast gratings, the fabrication difficulties can be minimized. Dispersion remains to be the most dominant source in the system of data loss. From the aspects of reflectivity, bandwidth, dispersion and non linearity, using high contrast gratings in waveguide approach is widely popular. Modified approach involves the high contrast gratings with high index material surrounded by a low-index material. The refractive index difference is maintained high that is greater than 2.4 which provides high reflectivity. Parameters on which reflectivity of waveguide mainly depends are grating thickness (tg), grating period (Λ), and duty cycle (η). Important design attribute is the sub wavelength size of gratings.