Optical properties of (Al,Ga)As/GaAs multiple quantum well planar waveguides and the fabrication of single-mode rib waveguides and directional couplers by reactive ion etching

An anisotropic absorption edge was observed in an (Al,Ga)As/GaAs multiple quantum well double-heterostructure (MQW-DH) single-mode planar optical waveguide. Single-mode rib waveguides and directional couplers were fabricated by SiCl(4) reactive ion etching. The results were found to be consistent with the assumption that the refractive index of the MQW structure for TE propagation is given by the weighted rms average value of the refractive indices of the constituent layers.