Optical transitions of the Mg acceptor in GaN

We report on the optical transitions of the neutral, paramagnetic Mg accept or in GaN, Its identification is based on the magnetic circular dichroism o f the absorption combined with optically detected magnetic resonance (ODMR) , Close to the band-gap energy, the transition from the Mg-0 ground state t o the neutral-acceptor-bound exciton state (A(0)X) is observed. In addition , the hole-ionisation transition Mg-0 + hv --> Mg- + h is detected in the i nfrared spectral range. The g-values and the anisotropy of the Mn accepters agree with those derived by luminescence-detected ODMR.