Enhanced photoluminescence from InAs/GaAs surface quantum dots by using a Si-doped interlayer

摘要

Photoluminescence (PL) of InAs/GaAs surface quantum dots (QDs) is enhanced by implanting a silicon-doped GaAs interlayer beneath surface QDs. It is observed that setting the doping concentration to 2.3 x 10(17) cm(-3) in the doped GaAs interlayer spaced 10 nm from the surface QDs results in optimal QD PL, i.e., highest intensity and narrowest linewidth. This improvement is attributed to the effective enhancement of the photo-excited carrier capture into the surface QDs and a filling of surface states due to free-carrier transfer from the doped GaAs layer to the surface QDs.