Generation of very flat optical frequency combs from continuous-wave lasers using cascaded intensity and phase modulators driven by tailored radio frequency waveforms

摘要

We demonstrate a scheme based on a cascade of lithium niobate intensity and phase modulators driven by speciallyntailored RF waveforms to generate an optical frequency comb with very high spectral flatness. In this Letter, wendemonstrate a 10 GHz comb with 38 comb lines within a spectral power variation below 1 dB. The number of combnlines that can be generated is limited by the power handling capability of the phase modulator, and this can be scalednwithout compromising the spectral flatness. Furthermore, the spectral phase of the generated combs in our schemenis almost purely quadratic, which, as we will demonstrate, allows for high-quality pulse compression using onlynsingle-mode fiber.