An ultra-flat, low-noise and linearly polarized fiber supercontinuum source covering 670 nm-1390 nm
preprintposted on 17.03.2021, 13:13 by Etienne Genier
We report an octave-spanning coherent supercontinuum (SC) fiber laser with excellentnoise and polarization properties. This was achieved by pumping a highly birefringent all-normaldispersion (ANDi) photonic crystal fiber with a compact high-power ytterbium femtosecond laserat 1049 nm. This system generates an ultra-flat SC spectrum from 670 nm to 1390 nm with apower spectral density higher than 0.4 mW/nm and a polarization extinction ratio of 17 dB acrossthe entire bandwidth. An average pulse-to-pulse relative intensity noise (RIN) down to 0.54%from 700 nm to 1100 nm has been measured and found to be in good agreement with numericalsimulations. This highly-stable broadband source could find strong potential applications inbiomedical imaging and spectroscopy where improved signal to noise ratio is essential.