A long-term frequency-stabilized erbium-fiber-laser-based optical frequency comb with an intra-cavity electro-optic modulator |
(a) Residual fluctuations of the 4th harmonic of the repetition rate. The gate time is 1 s and the dead-time between samplings is about 0.2 s; (b) in-loop frequency stability of 4 f r, measured with different gate (solid red triangle for 1 s, empty round for 2 s, 4 s, 8 s, and 16 s) times and measurement noise floor (solid black square). |