Title :
A beat-frequency tunable dual-mode fiber-Bragg-grating external-cavity laser
Author :
Wang, Wei ; Cada, Michael ; Seregelyi, Joe ; Paquet, Stephane ; Mihailov, Stephen J. ; Lu, Ping
Author_Institution :
Dalhousie Univ., Halifax, NS, Canada
Abstract :
A dual-mode external cavity laser employing two spatially separated fiber Bragg gratings has been investigated. We experimentally demonstrated that, without utilizing polarization separation techniques, a closely spaced (∼0.3 nm) dual-mode emission can be stabilized if a specific in-phase relation between the external feedbacks and the gain chip facet residual feedback is satisfied at both lasing wavelengths. The radio-frequency (RF) beat signal generated by the dual-mode optical signal had a typical extinction ratio of 25 dB above the noise floor and a 3-dB linewidth of approximately 2 MHz. The RF beat signal had a frequency tuning range of 200 MHz, where the dual-single-mode spectrum can be maintained.
Keywords :
Bragg gratings; fibre lasers; laser cavity resonators; laser feedback; laser modes; laser stability; laser tuning; microwave photonics; optical fibres; semiconductor lasers; beat-frequency tuning; dual-mode external-cavity laser; extinction ratio; fiber Bragg gratings; gain chip facet residual feedback; radio-frequency beat signal; Fiber lasers; Laser feedback; Optical feedback; Optical fiber polarization; Optical noise; RF signals; Radio frequency; Signal generators; Stimulated emission; Tunable circuits and devices; External cavity lasers (ECLs); fiber Bragg gratings (FBGs); microwave photonics and beat signals;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2005.858140
