Larsen, Casper3; Sørensen, Simon Toft1; Noordegraaf, Danny1; Hansen, K. P.4; Mattsson, Kent Erik1; Bang, Ole1
1 Department of Photonics Engineering, Technical University of Denmark2 Fiber Sensors and Supercontinuum Generation, Department of Photonics Engineering, Technical University of Denmark3 Risø National Laboratory for Sustainable Energy, Technical University of Denmark4 NKT Photonics A/S
Continuous wave (CW) pumped supercontinuum generation depends strongly on the zero-dispersion wavelength (ZDW) of the fiber due to the low peak power. Here we study several photonic crystal fibers by use of a gain-switched CW pump laser and investigate for what power level the supercontinuum reaches the silica mid-infrared loss edge and the bandwidth becomes independent of the ZDW. We show that for a quasi-CW power of more than 350 W the loss edge limits the broadening, and at 500 W we obtain a variation of only 4% in the achieved bandwidth for fibers with a ZDW in a 50 nm region around the 1064 nm pump wavelength.