Accurate chromatic dispersion characterization of photonic integrated circuits

An accurate technique to characterize chromatic dispersion and its slope versus wavelength is reported. The method is based on a heterodyne Mach-Zehnder interferometer, which is immune to thermal phase noise by using a counterpropagating reference beam. Chromatic dispersion profiles are obtained over a broad wavelength region even in short waveguides with considerable loss. Conventional strip silicon waveguides as well as slotted geometries are considered. Theoretical simulations are also presented for comparison, which show good agreement with the experimental results.