Transmittance and time-of-flight study of AlxGa1-xAs-based photonic crystal waveguides - art. no. 153313

Transmittance spectra and reflectance at a few specific wavelengths of AlxG a1-xAs-based air-rod photonic crystal waveguides with partially perforated cladding layer were measured by using a wavelength-tunable cw laser and a t ime-of-flight method, respectively. A marked drop of the transmittance for TM-like mode is found in the Gamma -M direction, which arises from a band g ap. The overall results for many samples with different parameters can be e xplained in terms of a model of photonic band structures. The radiation los s out of the plane, which is a key problem for this type of waveguide, incr eases drastically with an increase of either the number of rows N or the ai r-filling factor f. Thus it is concluded that only those waveguides with N = 5 and f less than or equal to 0.35 might work well for controlling the ra diation field in some cases.