Dispersion flattening in a w-fiber
A method for dispersion-flattening in double-clad single-mode optical fibers is presented. The chromatic dispersion over the wavelength range [1.25 µm, 1.60 µm] is minimized for a w-fiber and also for a triangular-index fiber with a depressed inner cladding. The constraint that the first higher order mode should appear exactly at 1.25 µm is imposed. The full vector solution of Maxwell’s equations