All-fiber supercontinuum source operating at 1 mu m with combination of different PCFs

We demonstrate an all-fiber scheme for generating supercontinuum spectrum based on a combination method. The configuration employed a nonlinear photonic crystal fiber for dispersion pre-management, an Yb-doped gain fiber for amplification and a special tapered photonic crystal fiber for supercontinuum generation. This setup allows for the generation of highly coherent supercontinuum with 30-dB bandwidth covering from 800 to 1240 nm as well as dispersive waves at 480 nm and 540 nm. The initial pulses were centered at 1030 nm with average power of 90 mW and repetition rate of 216 MHz. Based on the generated supercontinuum and dispersive waves at 540 nm, an envelope-carrier phase offset frequency with signal to noise ratio up to 37 dB was detected by a standard f-2f interferometer. The high signal to noise ratio shows that the infrared supercontinuum and the dispersive waves were highly coherent. Such a robust supercontinuum source achieved at low energy would promote the application of laser comb in precision measurement.