A microstructure-fiber based optical parametric oscillator

Summary form only given. Parametric processes in /spl chi//sup (2)/ materials have long been used to generate light at wavelengths where conventional laser sources are not available. Here we report what we believe to be the first demonstration of a microstructure fibre (MF) based optical parametric oscillator (MFOPO). By pumping near the MF´s zero-dispersion wavelength, we obtain tunable radiation at wavelengths shorter than that of the pump. Cascaded four-wave mixing (FWM) is also observed, wherein the oscillating signal, the pump, and the idler create radiation at new wavelengths. By pumping an appropriately tailored MF with Ti:sapphire or other high-power laser sources, such cascaded FWM may provide a viable route for the generation of tunable blue-green light. Our experiment also provides a detailed study of one of the nonlinear processes occurring below the supercontinuum threshold.