Abstract The effects of intermixing Al 0.54Ga 0.46As/GaAs/Al 0.54Ga 0.46As quantum well (QW) enhanced by arsenic ion implantation and subsequent annealing have been investigated by photoluminescence and photo-modulated reflectance measurements. Comparing with as-grown QW, obvious blueshifts of all the transitions were observed. The H 22 transition was found to be much less sensitive to the implantation doses than that of H 11. The experimental results are different from the theoretical results calculated by using the model of error function profile of Al composition. The results are fruitful for understanding the potential profile after intermixing enhanced by arsenic ion implantation, and also for the application of implantation enhanced intermixing effects on devices, such as QW lasers and photodetectors, opto-nonlinear devices, etc..