Time Resolved Studies of Proton Irradiated Quantum Dots

The effects of proton irradiation on carrier dynamics were measured by time-resolved photoluminescence on InGaAs/GaAs quantum dot structures with different dot density and substrate orientation, as well as on InAlAs/AlGaAs quantum dots. Results were compared to irradiation effects on carrier dynamics in thin InGaAs quantum wells. We find that carrier lifetimes in QDs are much less affected by proton irradiation than in quantum wells, which can be attributed to the three-dimensional carrier confinement in quantum dots.