Numerical modeling of experimentally fabricated InAs/GaAs quantum rings

Single sub-band model for InAs/GaAs quantum rings (QR), with the electron effective mass dependent on the confinement energy by the Kane formula is applied for numerical simulation of the capacitance-voltage ( CV) spectroscopy experiments. Geometrical parameters chosen for the model are based on the fabrication process for InAs/GaAs QD/QR. The 3D confined energy problem is solved numerically by the finite element method. Obtained results for QR single energy levels are in a good agreement with CV measurements. Evaluated magnitude of the electron effective mass is correlates with the FIR spectroscopy data. These results are compared with the existing 2D model calculations. Theoretical estimates for the addition to a ground state energy of the QR in external magnetic field are given, and compared with the experimental CV data.