Magnetoexcitons in planar type-II quantum dots in a perpendicular magnetic field

We study an exciton in a type-II quantum dot, where the electron is confined in the dot, but the hole is located in the barrier material. The exciton properties are studied as a function of a perpendicular magnetic field using a Hartree-Fock mesh calculation. Our model system consists of a planar quantum disk. Angular momentum (l) transitions are predicted with increasing magnetic field. We also study the transition from a type-I to a type-II quantum dot which is induced by changing the confinement potential of the hole. For sufficiently large magnetic fields a reentrant behavior is found from $l_h=0\mathrm{}$ to $l_h\ne 0$ and back to $l_h=0,$ which results in a transition from type II to type I.