Accurate chromatic dispersion characterization of nanophotonic waveguides with thermal phase noise cancellation

We report an experimental technique for accurate characterization of chromatic dispersion and its slope versus wavelength. The system consists of a fiber-based heterodyne Mach-Zehnder interferometer with a counter-propagating beam which is used to cancel the thermal phase noise. Three different silicon-based waveguides are characterized, obtaining a good agreement with theoretical simulations.