Two Wavelength Disordered Quantum Well Photodetector.

A GaAs/AlGaAs waveguide photodetector combining disordered and as-grown quantum well photodiodes is described. The disordered section serves both as a short wavelength photodiode and as a passive waveguide to transmit longer wavelengths to the as- grown section. Optical absorption and photocurrent spectra demonstrated the absorption edge shift edge shift due to disordering and the two wavelength-band selectivity of the device.