High power supercontinuum generation in tapered photonic crystal fibers

Tapering of photonic crystal fibers has proven to be an effective way of blueshifting the dispersive wavelength edge of a supercontinuum spectrum down in the deep-blue. In this contribution we will discuss the underlying mechanisms of supercontinuum generation in tapers. We show, by introducing the concept of a group-acceleration mismatch, that for a given taper length, the downtapering section should be as long as possible to enhance the amount of blueshifted light.

We also discuss the noise properties of supercontinuum in uniform and tapered fibers and we demonstrate that the amplitude noise at the spectral edges of the generated supercontinuum is at a constant level independent on the pump power in both tapered and uniform fibers.