Loss measurements in intermixed InGaAs/AlGaInAs multiple-quantum-well ridge waveguides

A study of the losses in InGaAs/AlGaInAs multiple-quantum-well ridge waveguides band edge shifted by quantum well intermixing is presented. The intermixing process is based on point defects generated on the sample surface during the deposition of sputtered SiO/sub 2/ and a subsequent rapid thermal annealing. It is demonstrated that for small wavelength shifts (60-80 nm), losses are considerably lower than in samples with maximum band edge shift (150 nm). Minimum losses of 6 dB/cm have been measured.