Phase locking of a mode-locked titanium-sapphire laser-based optical frequency comb to a reference laser using a fast piezoelectric actuator

• Published in: Applied optics. Optical technology and biomedical optics Vol. 56; no. 12; p. 3615
• Main Authors: Hatanaka, Shuhei, Sugiyama, Kazuhiko, Mitaki, Masatoshi, Misono, Masatoshi, Slyusarev, Sergey N, Kitano, Masao
• Format: Journal Article
• Language: English
• Published: United States 20.04.2017
• ISSN: 2155-3165
• DOI: 10.1364/ao.56.003615

We phase lock an octave-spanning optical frequency comb, generated using a mode-locked titanium-sapphire laser and a photonic-crystal fiber, to a continuous-wave laser line-narrowed to a reference cavity. To phase lock the pulse-repetition frequency, the cavity length of the mode-locked laser is controlled by using a fast piezoelectric-actuated mirror of a servo bandwidth up to 80 kHz. The residual phase noise is 0.35 rad, and 89% of the power is concentrated to the carrier. To apply the system to optical frequency-ratio measurements and to evaluate the phase locking, a simultaneous frequency measurement of the beat between the other mode of the comb and another laser line-narrowed to a different resonance of the common reference cavity is demonstrated.