Guided Wave Optical Components and Devices

CHAPTER 16

Enhancing Photosensitivity in Optical Fibers

Nirmal K. Viswanathan^*,     Photonics Division, IRDE, Dehradun, India

1 INTRODUCTION

Photosensitivity in optical fiber enables fabrication of gratings and grating-based devices that are critical components in optical communications networks. The intrinsic photosensitivity in standard single-mode (SSM) telecommunication fiber is typically low (Δn ≈ 3E⁻⁵). As a result, several methods of enhancing the fiber photosensitivity have been actively researched over the past decade [1, 2]. One of the major areas of research has been to develop intrinsically photosensitive fiber by increasing the germanium (Ge) content in the fiber core and also by co-doping with materials such as boron, phosphorous, ...