Frequency stabilization of multiwavelength lasers based on Pound-Drever-Hall technique

Frequency stability of laser sources is critical in ensuring laser-based measurement accuracy and reliability. In this paper, we report a method to assure high frequency stability of multi-wavelength lasers through the Pound-Drever-Hall technique. Three lasers with wavelength spacing of about 5G and 15nm around 1.55μm were simultaneously locked to the same Fabry-Pérot cavity with free spectral range of 5G. When locked, the laser frequencies were observed to drift all within 200 kHz, validating the feasibility of the system design. Frequency-locking of more lasers with different wavelengths can be realized to satisfy the requirement of different applications in this way.