B. Van Hattem, P. Corfdir, P. Brereton, P. Pearce, A. M. Graham, M. J. Stanley, M. Hugues, M. Hopkinson, R. T. Phillips
We present a three-dimensional magneto-photoluminescence study on neutral and charged excitons confined to InAs/GaAs quantum dots. Our investigation relies on a confocal setup that allows tuning arbitrarily the angle between the applied magnetic field and the sample growth axis. First, from experiments on neutral excitons and trions, we extract the in-plane and on-axis components of the Land\'e tensor for electrons and holes in the s-shell. Then, based on the doubly negatively charged exciton magneto-photoluminescence we show that the p-electron wave function spreads significantly into the GaAs barriers. We also demonstrate that the p-electron g-factor depends on the presence of a hole in the s-shell. The magnetic field dependence of triply negatively charged excitons photoluminescence exhibits several anticrossings, as a result of coupling between the quantum dot electronic states and the wetting layer. Finally, we discuss how the system evolves from a Kondo-Anderson exciton description to the artificial atom model when the orientation of the magnetic field goes from Faraday to Voigt geometry
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http://arxiv.org/abs/1302.6512
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