on ZnSe by molecular beam epitaxy. Applying a tilted magnetic field, all four levels of the
ground state are detected simultaneously. The zero-field separation between the optically
forbidden and allowed doublets ranges between 1.7 and 1.9 meV and is crucially influenced
by the finite energy barrier at the heterointerface as well as the existence of a wetting layer.
The energy splitting within the allowed doublet (200 μeV) is substantially larger than for the …