Measurement of the profiles of disorder-induced localized resonances in photonic crystal waveguides by local tuning

Near the band edge of photonic crystal waveguides, localized modes appear due to disorder. We demonstrate a new method to elucidate spatial profile of the localized modes in such systems using precise local tuning. Using deconvolution with the known thermal profile, the spatial profile of a localized mode with quality factor (Q) > 105 is successfully reconstructed with a resolution of 2.5 μm