EPITAXIAL-GROWTH AND OPTICAL-TRANSITIONS OF CUBIC GAN FILMS

Single-phase cubic GaN layers are grown by plasma-assisted molecular-b eam epitaxy. The temperature dependence of the surface reconstruction is elaborated. The structural stability of the cubic growth in depende nce of the growth stoichiometry is studied by RHEED measurements and n umerical simulations of the experimental RHEED patterns. Growth oscill ations on cubic GaN are recorded at higher substrate temperatures and nearly stoichiometric adatom coverage. Photoluminescence reveals the d ominant optical transitions of cubic GaN and, by applying an external magnetic field, their characteristic g factors are determined.