High-Speed Photonics Interconnects

3	Silicon Photonic Bragg Gratings
Xu Wang, Wei Shi, and Lukas Chrostwoski

CONTENTS

3.1  Introduction

3.2  Uniform Bragg Gratings in Silicon Waveguides

3.2.1  Theory

3.2.2  Integration in Silicon Waveguides

3.2.2.1  Strip Waveguide Gratings

3.2.2.2  Rib Waveguide Gratings

3.2.3  Complementary Metal-Oxide Semiconductor (CMOS)-Compatible Fabrication

3.2.3.1  Fabrication Uniformity

3.2.3.2  Lithography Simulation

3.3  Applications of Bragg Gratings in Silicon Photonics

3.3.1  Nonuniform Waveguide Grating Structures

3.3.1.1  Sampled Gratings

3.3.1.2  Phase-Shifted Gratings

3.3.2  Grating-Assisted, Contradirectional Couplers

3.3.2.1  Principle

3.3.2.2  Add-Drop Filters Using Contradirectional Couplers

3.3.2.3  Modeling of Silicon Contradirectional ...