Electronic and excitonic properties of self-assembled semiconductor quantum rings

Theoretical analysis of the electron energy spectrum and the magnetization in a strained InxGa1-xAs/GaAs selfassembled quantum ring (SAQR) is performed using realistic parameters, determined from the cross-sectional scanning-tunneling microscopy characterization. The Aharonov-Bohm oscillations in the persistent current have been observed in low temperature magnetization measurements on these SAQRs. The effect of the Coulomb interaction on the energy spectra of SAQRs is studied for rings with two electrons and with an exciton. Our analysis of the photoluminescence spectrum in magnetic fields up to 30 T shows that the excitonic properties strongly depend on the anisotropic shape, size, composition and strain of the SAQRs and is in a good agreement with the experimental data.

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