Coherent Visible Femtosecond Supercontinuum in Dispersion-Tailored Photonic Crystal Fiber

We report efficient visible supercontinuum (SC) generated from a dispersion-tailored air-suspended-core photonic crystal fiber, using an 800-nm Ti:sapphire laser with a pulse duration of ~29 fs and a repetition rate of 80 MHz. The conversion efficiency of pump-to-visible SC has been measured to be as high as 29 % in a 10-cm long fiber, with the visible SC power of 28.4 mW. The spectral interference measurement indicates that the generated SC possesses a high degree of coherence greater than 0.91, which is supported by the numerical simulations. The highly coherent SC is due to the combination of ultrafast femtosecond pump, dispersion–tailored photonic crystal fiber, and the ultra-high shot-to-shot phase stability of the pump.