We report on a simple, compact, and robust 780 nm distributed Bragg reflector laser with subkilohertz intrinsic linewidth. An external cavity with optical path length of 3.6 m, implemented with an optical fiber, reduces the laser frequency noise by several orders of magnitude. At frequencies above 100 kHz the frequency noise spectral density is reduced by over 33 dB, resulting in an intrinsic Lorentzian linewidth of 300 Hz. The remaining low-frequency noise is easily removed by stabilization to an external reference cavity. We further characterize the influence of feedback power and current variation on the intrinsic linewidth. The system is suitable for experiments requiring a tunable laser with narrow linewidth and low high-frequency noise, such as coherent optical communication, optical clocks, and cavity QED experiments.
© 2012 Optical Society of America
Lasers and Laser Optics
Original Manuscript: February 9, 2012
Revised Manuscript: March 23, 2012
Manuscript Accepted: March 24, 2012
Published: May 30, 2012
Qian Lin, Mackenzie A. Van Camp, Hao Zhang, Branislav Jelenković, and Vladan Vuletić, "Long-external-cavity distributed Bragg reflector laser with subkilohertz intrinsic linewidth," Opt. Lett. 37, 1989-1991 (2012)