Photonic crystal waveguides with semi-slow light and tailored dispersion properties

Lars H Frandsen,Peter I Borel,Jacob Fage-Pedersen,Andrei V Lavrinenko

doi:10.1364/oe.14.009444

Lars H Frandsen, Peter I Borel + Show 2 more

Open Access

https://doi.org/10.1364/oe.14.009444

Copy DOI

Journal: Optics Express	Publication Date: Jan 1, 2006
Citations: 384	License type: cc-by

Affiliation: Technical University of Denmark

Abstract

We demonstrate a concept for tailoring the group velocity and dispersion properties for light propagating in a planar photonic crystal waveguide. By perturbing the holes adjacent to the waveguide core it is possible to increase the useful bandwidth below the light-line and obtain a photonic crystal waveguide with either vanishing, positive, or negative group velocity dispersion and semi-slow light. We realize experimentally a silicon-on-insulator photonic crystal waveguide having nearly constant group velocity ~c(0)/34 in an 11-nm bandwidth below the silica-line.

Highlights

The intricate confinement of light in a photonic crystal waveguide (PhCW) [1] and its resulting dispersion properties offer sophisticated possibilities for realizing complex nanophotonic circuits
It has been demonstrated that the dispersion properties of PhCWs can be altered via a structural tuning of the waveguide geometry, typically, by changing the waveguide width or by introducing bi-periodicity [11, 12, 13]
Such dramatic changes of the PhCW may lead to multimode operation, decreased coupling efficiency to a photonic wire, and structural continuity problems in, e.g., bend and splitting regions

Summary

Introduction

The intricate confinement of light in a photonic crystal waveguide (PhCW) [1] and its resulting dispersion properties offer sophisticated possibilities for realizing complex nanophotonic circuits. It has been demonstrated that the dispersion properties of PhCWs can be altered via a structural tuning of the waveguide geometry, typically, by changing the waveguide width or by introducing bi-periodicity [11, 12, 13]. We show how the knowledge of the field distributions in a single-line defect (W1) PhCW can be exploited to tailor the dispersion properties of the fundamental even photonic bandgap (PBG) mode. In this way, one can realize a silicon-on-insulator (SOI) W1 PhCW with semi-slow light having a group velocity in the range ~(c0/15 – c0/100); vanishing, positive, or negative group velocity dispersion (GVD); and low-loss propagation in a practical ~5-15 nm bandwidth

Design aspects & modeling

Fabrication and experimental results

Findings

Conclusion