Splitting of electronic levels with positive and negative angular momenta in ${\mathrm{In}}_{0.53}$${\mathrm{Ga}}_{0.47}$As/InP quantum dots by a magnetic field

High excitation magnetoluminescence investigations have been performed on cylindrical ${\mathrm{In}}_{0.53}$${\mathrm{Ga}}_{0.47}$As/InP quantum dots with different diameters down to 30 nm. The magnetic field oriented normal to the quantum disks enhances the lateral confinement of the carriers inside of the dots, and splits energy levels with positive and negative angular momenta due to the Zeeman-like interaction. This splitting depends linearly on B, and is independent of the disk size. The increase of the lateral quantization of the carriers by the magnetic field, on the other hand, depends strongly on the dot diameter. The experimental results are in good agreement with the results of detailed numerical calculations. © 1996 The American Physical Society.