Continuous-wave tunable optical parametric generation in a photonic-crystal fiber

Continuous-wave and quasi-cw operation of tunable optical parametric generation has been demonstrated in a photonic-crystal fiber. The frequency shift of the generated sidebands, which arise from modulation instability, depends strongly on the detuning of the pump from the fiber's zero-dispersion wavelength. Over 30 nm of sideband tunability has been demonstrated using a 300 mW cw pump, and over 185 nm of tunability using a 1.6 W quasi-cw pump. Continuous wave and quasi-cw pumps eliminate the detrimental effects of pump-sideband walk-off. In the absence of walk-off it is the fluctuations in the index profile of the photonic-crystal fiber along its length that limit the tunable sideband range. (c) 2005 Optical Society of America.