학술논문

Low FSR Mode-Locked Laser Based on InP-Si3N4 Hybrid Integration
Document Type
Periodical
Source
Journal of Lightwave Technology J. Lightwave Technol. Lightwave Technology, Journal of. 39(24):7573-7580 Dec, 2021
Subject
Communication, Networking and Broadcast Technologies
Photonics and Electrooptics
Laser mode locking
Optical waveguides
Measurement by laser beam
Bragg gratings
Optical filters
Propagation losses
Semiconductor device measurement
Semiconductor lasers
frequency comb generation
mode-locked laser
semiconductor lasers
Language
ISSN
0733-8724
1558-2213
Abstract
Generation of optical frequency combs (OFC) using semiconductor laser sources has been an active research topic for years, since they offer good performances for many applications without the bulky and expensive aspects of ion doped fiber or crystal based laser sources. In this paper, we demonstrate the generation of low free spectral range mode-locked laser using hybrid III-V/Si 3 N 4 butt coupling. We start by describing the design and the fabrication process of the active R-SOA chip made at our laboratory, and the passive Si 3 N 4 chip having low losses measured to be around 6 dB/m. We then report the integration process and the results of passive mode locking. Our mode-locked laser has a repetition rate of 360 MHz, which is, to the best of our knowledge, the lowest repetition rate achieved for a hybrid integrated mode-locked laser. The frequency comb generated has a 30 dB bandwidth of 2.8 nm (349 GHz). Finally, we show the demonstration of active and harmonic mode locking up to the sixth harmonic.