Ultra-broadband multimode waveguide dispersion measurement

Integrated photonic waveguides serve as an ideal platform for nonlinear processes at high efficiency in a very compact footprint. Key to the design of such structures is the ability to precisely engineer waveguide dispersion properties. However, especially for novel materials, the unavailability in bulk dispersion data and fabrication inconsistencies often compromise numerical models, rendering waveguide design a challenge. To bridge this gap, we propose a technique based on white light interferometry that can not only quantify waveguide dispersion in a more than two-octave spectral range without relying on model assumptions from the visible to the mid-infrared region, but also enables multimodal measurements.