Quantum well intermixing and wavelength-shifting in GaAs lasers by proton irradiation

Proton irradiation with subsequent rapid thermal annealing has been used to create intermixing in GaAs-Al/sub 0.3/Ga/sub 0.7/As quantum wells. Good recovery in the photoluminescence signals is observed, indicating that very few residual defects are present after annealing. This process is then extended to selectively induce intermixing and thus shift the lasing wavelengths of GaAs-based graded-index separate-confinement-heterostructure quantum well lasers with no observable degradation in the current threshold characteristics. This is a simple and very promising technique of integrating lasers of different wavelengths for wavelength-division-multiplexing applications.