Properties of muonium defect centers in the III-V nitrides

Recent results are presented for the muonium analog of isolated hydrogen impurities in the III-V nitrides. The Mu+ and Mu- centers reside at sites anti-bonding to the N atom and the group III atom, respectively. Stable sites for each lie in the channel and metastable sites in the cage formed by the 2H stacking of the wurtzite structure. Data for AlN and GaN imply short-lived atomic-like Mu0 states and a shallow-donor Mu0 is observed in InN. Characteristic energies for motion, site changes and charge-state transitions are obtained from zero-field depolarization data. Results imply that Mu/H diffusion strongly depends on the charge state