Nearly arbitrary on-chip optical filters for ultrafast pulse shaping.

Ian W Frank,Yinan Zhang,Marko Loncar

doi:10.1364/oe.22.022403

Abstract

We demonstrate a reverse design method for realizing a broad range of optical filters based on integrated optical waveguides and experimentally verify example designs on a CMOS-compatible silicon-on-insulator (SOI) platform. The reflectance-based filters allow for control of both phase and amplitude of the optical response. Among this device's many potential applications we highlight and numerically demonstrate its use for ultrafast on-chip pulse shaping.

Highlights

The advent of photonic bandgap materials has led to incredible progress in the ability to confine and guide light [1,2,3]
We present a simple and fast method for designing such a structure. While this method can be generally applied to any material system where the refractive index profile can be controlled along one axis, we have concentrated on implementing arbitrary reflective filters in compact, on-chip silicon-on-insulator (SOI) waveguides. These integrated filters have myriad applications from on-chip signal routing to compact, ultra-fast pulse shaping [10]; the latter being of significant interest for high-speed optical communication and quantum control experiments [11]
In addition to allowing the design of arbitrary phase and amplitude filters these structures show a great promise in shaping ultrafast pulses as demonstrated through FDTD simulations

Summary

Introduction

The advent of photonic bandgap materials has led to incredible progress in the ability to confine and guide light [1,2,3]. The previously developed methods have operated either in broad stop and pass bands [4] or with extremely narrow-band – resonance – regimes [5] Additional fields such as plasmonics [6,7] and metamaterials [8,9], provide methods for designing structures that can manipulate light, but even there, we see limitations on the diversity of spectral response from a single device. We present a simple and fast method for designing such a structure While this method can be generally applied to any material system where the refractive index profile can be controlled along one axis, we have concentrated on implementing arbitrary reflective filters in compact, on-chip silicon-on-insulator (SOI) waveguides. These integrated filters have myriad applications from on-chip signal routing to compact, ultra-fast pulse shaping [10]; the latter being of significant interest for high-speed optical communication and quantum control experiments [11]

Reverse design method and refinements

Conclusions and future work