Noise suppression through extreme self-phase modulation in cascaded mid-IR supercontinuum generation

The soliton rich supercontinuum (SC) generated by a long pump pulse propagating in the anomalous dispersion region of a ZBLAN fibre, creates extreme broadening when coupled into a highly nonlinear glass fibre. The extreme broadening along with the low loss in a broad range of the mid-IR wavelength regime, and the newly discovered giant Raman red-shifting SPM wave [1] , [2] leads to efficient power transfer far into the mid-IR regime. We here present numerically evaluated noise properties of the SC generated in the As 2 Se 3 fibre, using an ensemble of 295 pump pulses (Gaussian shape, 2 m input wavelength, 4kW peak power, and 10ps 1/e width) into the ZBLAN fibre with one-photon-per-mode and 1% Relative Intensity Noise (RIN). The simulations are done in the generalized Nonlinear Schrödinger equation with the same model and fibre parameters as described in [1]. Most notably, the zero dispersion wavelength is at 1.56 m in the ZBLAN fibre, and at 6 m in the As 2 Se 3 fibre. The length of ZBLAN fibre is 40 meter, and the As 2 Se 3 is 1 meter long.