Open AccessChannel-spacing tunable silicon comb filter using two linearly chirped Bragg gratings
Author(s) -
Zhi Zou,
Linjie Zhou,
Xinwan Li,
Jianping Chen
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.019513
Subject(s) - optics , materials science , apodization , channel spacing , fiber bragg grating , comb filter , michelson interferometer , silicon , free spectral range , filter (signal processing) , refractive index , channel (broadcasting) , optical filter , interferometry , wavelength division multiplexing , optoelectronics , physics , wavelength , telecommunications , computer science , computer vision
We propose a novel silicon-based comb filter with tunable channel spacing using a Michelson interferometer consisting of a pair of apodized linearly chirped Bragg gratings (ALC-BGs). The channel spacing of the proposed comb filter can be continuously tuned with a large tuning range by changing the effective refractive index of one of the ALC-BGs through the thermo-optic effect. Our numerical calculation shows that the channel spacing can be continuously tuned form 8.21 nm to 0.19 nm with an out-of-band rejection ratio of greater than 30 dB.