Optical properties of magnetoexcitons in double quantum dots

Here we investigate the influence of a constant magnetic field on the energy levels and optical properties of excitons in a double quantum disk (quantum molecule). Taking into account the cylindrical symmetry of the double disk we calculate the wave functions and excitonic energies when the external constant magnetic field is applied along the symmetry axis. Having the eigenfunctions and eigenvalues and using the long-wave approximation we can compute all the optical functions. The double quantum dot is considered as one system rather than two interacting dots separated by narrow barrier. The screened Coulomb interaction between an electron and a hole is assumed. Since in the given structure the separation of the relative- and center-of-mass motion of the electron and the hole is not possible, we use an approach where the six-dimensional eigenvalue problem is transformed into the equivalent eigenvalue problem given by the system of the coupled two-dimensional second order differential equations. The so obtained differential equations are solved numerically. As an example, we give detailed results for a InP/InGaP double quantum dot. Satisfactory agreement with the available experimental data is obtained. Copyright The Author(s) 2015