Imaging of Iso-frequency Contours via Resonance-Enhanced Scattering in Near-Pristine Photonic Crystals

摘要

The iso-frequency contours of a photonic crystal are important for predictingand understanding exotic optical phenomena that are not apparent fromhigh-symmetry band structure visualizations. Here, we demonstrate a method todirectly visualize the iso-frequency contours of high-quality photonic crystalslabs that shows quantitatively good agreement with numerical resultsthroughout the visible spectrum. Our technique relies on resonance-enhancedphoton scattering from generic fabrication disorder and surface roughness, soit can be applied to general photonic and plasmonic crystals, or evenquasi-crystals. We also present an analytical model of the scattering process,which explains the observation of iso-frequency contours in our technique.Furthermore, the iso-frequency contours provide information about thecharacteristics of the disorder and therefore serve as a feedback tool toimprove fabrication processes.