Open AccessSilicon photonic grating-assisted, contra-directional couplers
Author(s) -
Wei Shi,
Xu Wang,
Cheng-Ju Lin,
Han Yun,
Yang Liu,
Tom BaehrJones,
Michael Hochberg,
Nicolas A. F. Jaeger,
Lukas Chrostowski
Publication year - 2013
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.21.003633
Subject(s) - coupled mode theory , optics , materials science , extinction ratio , optical circulator , fiber bragg grating , photonics , grating , circulator , photonic integrated circuit , resonator , silicon photonics , optoelectronics , power dividers and directional couplers , waveguide , wavelength , physics , refractive index
We demonstrate, in both theory and experiment, 4-port, electrically tunable photonic filters using silicon contra-directional couplers (contra-DCs) with uniform and phase-shifted waveguide Bragg gratings. Numerical analysis, including both intra- and inter-waveguide couplings, is performed using coupled-mode theory and the transfer-matrix method. The contra-DC devices were fabricated by a CMOS-photonics manufacturing foundry and are electrically tunable using free-carrier injection. A 4-port, grating-based photonic resonator has been obtained using the phase-shifted contra-DC, showing a resonant peak with a 3-dB bandwidth of 0.2 nm and an extinction ratio of 24 dB. These contra-DC devices enable on-chip integration of Bragg-grating-defined functions without using circulators and have great potential for applications such as wavelength-division multiplexing networks and optical signal processing.