Optical Signatures of Spin-Orbit Interaction Effects in a Parabolic Quantum Dot

We demonstrate here that the dipole-allowed optical absorption spectrum of a parabolic quantum dot subjected to an external magnetic field reflects the interelectron interaction effects when the spin-orbit (SO) interaction is also taken into account. We have investigated the energy spectra and the dipole-allowed transition energies for up to four interacting electrons parabolically confined, and have uncovered several novel effects in those spectra that are solely due to the SO interaction.

Figure 1

Energy spectra (left panel) and dipole-allowed transition energies (right panel) for two interacting electrons confined in an InAs quantum dot and for various values of the SO coupling strength $\alpha$ [meV nm]. The solid dots in the energy spectrum identify the energy levels involved in transitions that correspond to the lowest branches of the absorption spectra (in the right panel). In the right panels, the size of the points in the figures is proportional to the calculated intensity.

Figure 2

Same as in Fig. 1, but for three interacting electrons in a quantum dot.

Figure 3

Same as in Fig. 1, but for four interacting electrons in a quantum dot.