Characterizing a Fiber-Based Frequency Comb With Electro-Optic Modulator

Laboratoire National de Métrologie et Essais-Systèmes de Référence Temps et Espace (LNE-SYRTE), Observatoire de Paris, Centre National de la Recherche Scientifique, Université Pierre et Marie Curie, Paris, France.
IEEE transactions on ultrasonics, ferroelectrics, and frequency control (Impact Factor: 1.51). 03/2012; 59(3):432-8. DOI: 10.1109/TUFFC.2012.2212
Source: PubMed


We report on the characterization of a commercial- core fiber-based frequency comb equipped with an intracavity free-space electro-optic modulator (EOM). We investigate the relationship between the noise of the pump diode and the laser relative intensity noise (RIN) and demonstrate the use of a low-noise current supply to substantially reduce the laser RIN. By measuring several critical transfer functions, we evaluate the potential of the EOM for comb repetition rate stabilization. We also evaluate the coupling to other relevant parameters of the comb. From these measurements, we infer the capabilities of the femtosecond laser comb to generate very-low-phase-noise microwave signals when phase-locked to a high-spectral-purity ultra-stable laser.

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Available from: Y. Le Coq, Apr 04, 2014
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