Tunable ring laser with internal injection seeding and an optically-driven photonic crystal reflector Jie Zheng,1 Chun Ge,1Clark J. Wagner,1 Meng Lu,2 Brian T. Cunningham,1,3 J. Darby Hewitt,1,*and J. Gary Eden1 1Department of Electrical and Computer Engineering, University of Illinois, Urbana, Illinois 61801, USA 2SRU Biosystems, 14-A Gill Street, Woburn, Massachusetts 01810, USA 3Department of Bioengineering, University of Illinois, Urbana, Illinois 61801, USA *
[email protected] Abstract: Continuous tuning over a 1.6 THz region in the near-infrared (842.5-848.6 nm) has been achieved with a hybrid ring/external cavity laser having a single, optically-driven grating reflector and gain provided by an injection-seeded semiconductor amplifier. Driven at 532 nm and incorporating a photonic crystal with an azobenzene overlayer, the reflector has a peak reflectivity of ~80% and tunes at the rate of 0.024 nm per mW of incident green power. In a departure from conventional ring or external cavity lasers, the frequency selectivity for this system is provided by the passband of the tunable photonic crystal reflector and line narrowing in a high gain amplifier. Sub - 0.1 nm linewidths and amplifier extraction efficiencies above 97% are observed with the reflector tuned to 842.5 nm. ©2012 Optical Society of America OCIS codes: (050.5298) Photonic crystals; (140.3520) Lasers, injection-locked; (140.3560) Lasers, ring; (140.3480) Lasers, diode-pumped. References and links 1. J. W. Crowe and R. M. Craig, Jr., “GaAs laser linewidth measurements by heterodyne detection,” Appl. Phys. Lett. 5(4), 72–74 (1964).