ZEEMAN SPECTROSCOPY OF V-3+-LUMINESCENCE IN ZNO

ZnO crystals exhibit in the near infrared spectral region a well-known but up to now contradictorily discussed luminescence structure. We show on the basis of carefully performed fine structure measurements in dependence on polarizations, temperatures and magnetic fields that the mentioned luminescence is due to the 3T2(F)-3A2(F) transition of isolated substitutional V3+ on the cation place. The observed fine-structures show the action of a strong Jahn-Teller coupling of epsilon-modes to the 3T2(F) term. The excitation spectra prove the presence of V3+ in the unexcited crystal. In the excited 3T1(F) term an interaction between distinct phonon modes and the phonon continua takes place, resulting in the occurrence of Fano resonances in the excitation spectra.