Low-Loss Two-Dimensional GaAs Epitaxial Waveguides at 10.6-μm Wavelength

The successful fabrication of low-loss two-dimensional GaAs epitaxial waveguides by chemical etching for use in integrated optics at 10.6 μm is reported. Selective excitation of specific E_pq^y modes was observed by placing the prism at specific angles in the horizontal plane. Loss measurements showed no increase in attenuationfor lower order E_pq^y modes (as compared to corresponding one-dimensional waveguide modes) when the guide width is 50 μm. As the guide width is reduced, there is a significant increase in attenuation as p increases.