A long-term frequency-stabilized erbium-fiber-laser-based optical frequency comb with an intra-cavity electro-optic modulator

摘要

We demonstrate an optical frequency comb based on an erbium-doped-fiberfemtosecond laser with the nonlinear polarization evolution scheme. Therepetition rate of the laser is about 209 MHz. By controlling an intra-cavityelectro-optic modulator and a piezo-transducer, the repetition rate can bestabilized with high servo bandwidth in a range of 3 kHz, enabling long-termrepetition rate phase-locking. The in-loop frequency stability of repetitionrate is about 1.6E-13 at 1 second integration time, limited by the measurementsystem; and it is inversely proportional to integration time in short term.Furthermore, using a common path f-2f interferometer, the carrier envelopeoffset frequency of the frequency comb is obtained with a signal-to-noise ratioof 40 dB in 3 MHz resolution bandwidth. Stabilized carrier envelope offsetfrequency exhibits a deviation of 0.6 mHz at 1 second integration time.