High-order dispersion mapping of an optical fiber.

We report on measurements of high-order dispersion maps of an optical fiber, showing how the ratio between the third and fourth-order dispersion (β/β) and the zero-dispersion wavelength (λ) vary along the length of the fiber. Our method is based on Four-Wave Mixing between short pulses derived from an incoherent pump and a weak laser. We find that the variations in the ratio β/β are correlated to those in λ.

Shift of zero-dispersion wavelength in bent optical fibers.

The understanding of how bending modifies the dispersion of optical fibers, in particular, the zero-dispersion wavelength (λ), is essential in the development of compact nonlinear optical devices such as parametric amplifiers, wavelength converters, soliton lasers and frequency comb generators. Typically, substantial variations in the parametric gain and/or conversion efficiency are significant for changes in λ of ~0.1 nm, which occur for variations on the bending radius (Rb) of 1 cm or less.