Photonic crystal channel waveguides in InP

We have fabricated high-quality planar photonic crystal defect waveguides in InP/InGaAsP material. Using Fourier analysis of the Fabry-Perot fringes obtained in transmission, we derive the propagation losses. Values as small as 1.8 dB/mm for waveguides consisting of 3 rows of missing holes ("W3") were measured. To the best of our knowledge, this is the smallest loss in III-V semiconductor photonic crystal waveguides reported to date. We believe that the reduction in losses is due to the high quality of etching carried out using a new regime of chemically assisted ion beam etching.