Effects of magnetic field on multi-excitonic structures in GaAs quantum dots

We have studied multi-excitonic energy levels confined in single GaAs/AlGaAs quantum dots grown by modified droplet epitaxy via micro-photoluminescence (μPL) measurements under a magnetic field. From the excitation intensity dependence of the μPL spectrum of a single GaAs Quantum dot, it is possible to see the emissions from multi-excitonic energy levels. By applying a magnetic field, splitting of the exciton line is observed. Similarly to the exciton line, the multi-exciton lines split with increasing magnetic field. It can be considered that the splitting of the multi-exciton lines arises from the exciton Zeeman splitting essentially.