New mechanism for light concentration observed in topological photonic crystals

The results of our close collaboration with the groups of Gennady Shvets (Cornell) and Kobus Kuipers (TU Delft) were published in Science Advances today. We report the observation of a new mechanism for concentrating light in a wavelength-sized volume, using suppression of back-reflections at the termination of an on-chip topological photonic waveguide. This work was inspired by the theoretical prediction of broadband field enhancement at the end of a unidirectional waveguide, which is fundamentally different from traditional approaches for light confinement with a cavity. Following the predictions of our collaborators from Cornell, we now observed that this mechanism occurs in topological photonic crystals that feature suppressing of back-reflection at a suitably terminated waveguide. Check out our news item, and the paper itself. Congrats to first authors Daniel Muis and Yandong Li, and also René Barczyk and Sonakshi Arora!