Dispersion and modulation of the linear optical properties of GaAs-AlAs superlattice waveguides using quantum-well intermixing

We report on the large modulation of the optical properties of a 14:14 monolayer GaAs-AlAs superlattice waveguide following quantum-well intermixing. Low-temperature photoluminescence measurements illustrate a large 169-meV differential blue-shift obtained between the disordering-suppressed and disordering-enhanced materials. Effective index measurements are presented as a function of polarization, for both the as-grown and disordered material for near-bandedge and half-bandedge wavelengths, which is the wavelength range 775-1550 nm. The largest effective refractive index shift observed was 9×10^-2 which exceeds that previously reported for disordered AlGaAs ternary multilayer structures, and illustrates the potential of the superlattice for the fabrication of etch-free, planar optical components with large index contrast.