Tapered Bragg Gratings Research Articles

Integrated Dispersion Compensator Based on Apodized SOI Bragg Gratings

In this letter, we present the design and realization of an integrated drop filter with optimized tapered Bragg gratings for the compensation of the optical chromatic dispersion. An apodization profile for the gratings has been determined for an optimal reduction of the group delay ripple and the enhancement of the system performance. The apodization has been carried out varying the width of the grating trenches at the two ends with a sine profile and the principle has been experimentally demonstrated. The device permits a dispersion compensation of 480 ps/nm and an error-free detection of a DQPSK signal up to 30 Gbaud.

Continuously tunable delay line based on SOI tapered Bragg gratings

The realization of an integrated delay line using tapered Bragg gratings in a drop-filter configuration is presented. The device is fabricated on silicon-on-insulator (SOI) rib waveguides using a Deep-UV 248 nm lithography. The continuous delay tunability is achieved using the thermo-optical effect, showing experimentally that a tuning range of 450 ps can be obtained with a tuning coefficient of -51 ps/°C. Furthermore the system performance is considered, showing that an operation at a bit rate of 25 Gbit/s can be achieved, and could be extended to 80 Gbit/s with the addition of a proper dispersion compensation.

Influence of introducing chirp on bistable characteristics of linear negative tapered Bragg gratings

Based on the coupled mode theory, the influence of introducing the chirp on the bistable characteristics of linear negative tapered Bragg gratings is investigated. The results show that introducing positive chirp improves the bistable performance of linear negative tapered Bragg gratings, and the bistable performance can be further optimized by reasonably selecting the length of the linear negative tapered Bragg gratings with positive chirp.