2.1. Introduction

Within actual Photonic Integrated Circuits (PICs), light confinement is provided by the index contrast that exists between different materials and according to the geometry of a structure. This index contrast mechanism limits the desirable PIC size reduction (performances are then degraded) and the integration of optical functions. Within the periodic environment of a Photonic Crystal (PhC), light confinement can be obtained based on an intentional defect included in the PhC matrix. Devices implementing this multiple Bragg reflection mechanism may overcome these limits [LOU 05].

This chapter is an attempt to demonstrate that passive as well as active optical functions required in Telecoms networks can be fulfilled using PhC-based devices. Passive functions such as guiding, coupling and filtering as well as active functions such as emission and amplification are investigated here.

These examples demonstrate that compactness and monolithic integration can actually be reached with PhC-based devices. For the 1.3 1.5 m Telecom wavelength domain, as emission is also addressed, all the structures reported here are fabricated on InP-based materials.

This chapter is divided into three sections:

• section 2.2 introduces the concepts that underlie device design, and explains the various performances that are expected of applications. For more in-depth exploration of the concepts, the reader is referred to Chapter 1;

• section 2.3 presents the technology required for the fabrication of 2D-PhC structures on InP substrate;

• section 2.4, the largest section, details the characterization of passive and active operating devices. Attention is paid to spectrally...