Compound cavity measurement of transmission and reflection of a tapered single-line photonic-crystal waveguide

Measurements on a single-line defect photonic crystal waveguide demonstrate propagation losses as low as 140 cm(-1) and coupling efficiency to a ridge access guide increased from 20% to 50% thanks to a tapered access. These results are obtained by analyzing the internal cavities created by residual reflections, hence, requiring a single sample. They are nevertheless crosschecked by measurements on distinct samples by the Fabry-Perot resonance method. (C) 2003 American Institute of Physics.