Soliton self-frequency shift effects in photonic crystal fibre

Abstract
Using a femtosecond Ti:sapphire laser operating at a wavelength of 810nm we have demonstrated infrared generation in photonic crystal fibre at distinct wavelengths which can be attributed to the soliton self-frequency shift effect. The maximum observed shift produced spectra centred at 1260nm and the frequency-shifted light accounted for up to 80% of the fibre output power. We show that the shifts can be explained by the dispersion properties of the fundamental and higher-order waveguide modes of the fibre.