Resonant photoemission of rare earth doped GaN thin filmsS.R. McHale, J.W. McClory, J.C. Petrosky, J. Wu, R. Palai, Ya.B. Losovyj and P.A. DowbenEur. Phys. J. Appl. Phys., 56 1 (2011) 11301DOI: https://doi.org/10.1051/epjap/2011110235