Low-loss high-purity GaAs waveguides for monolithic integrated optical circuits at GaAs laser wavelengths

Attenuation measurements in epitaxial n-GaAs waveguides of different purity have been made near the absorption edge. These measurements show that losses of less than 2 cm−1 can be achieved at energies within 50 meV of the band edge using material with ND+NA⩽2×1015 cm−3. These loss values are low enough to permit the use of GaAs waveguides in some integrated optical circuits and, in addition, are significantly lower than those published for AlxGa1−xAs waveguides of similar purity at energies comparably near the absorption edge.