Supercontinuum generation in the range 1.6 — 2.4 μm using standard optical fibres

Experimental evidence is presented that standard optical fibres can be used to efficiently convert nanosecond pulses at 1.59 μm to a supercontinuum in the range 1.6 — 2.4 μm. The highest efficiency of conversion to wavelengths above 2 μm, 38%, has been offered by a multimode graded-index fibre. The spectral density of average power in the range 2 — 2.35 μm in this fibre is about 1 mW nm^-1 and that of peak power is about 10 W nm^-1. In all the fibres studied, the practical long-wavelength limit of generation is 2.35 μm.