Steering optical comb frequencies by rotating the polarization state

We demonstrate a new approach to steer the frequencies of a nonlinear polarization-rotation mode-locked laser, where a specially designed intrcavity electro-optic modulator tunes the polarization state of the laser signal. This approach not only results in the broadband associated with high performance, but also results in a large dynamic range associated with good robustness. Our experimental results show that frequency control dynamic ranges are at least one order of magnitude larger than those of the previous ultra-fast frequency control techniques, reaching hundreds of hertz and hundreds of megahertz for repetition rate (fr) and carrier-envelope-offset frequency (fceo), respectively.