Optical studies on the incorporation of carbon as a dopant in cubic GaN - Soares, J A N T; Fernandez, J R L; Cerdeira, F; Brasil, M J S P; Santos, A M; Noriega, Odille Cue; Leite, J. R.; As, Donat Joseph; Köhler, U; Potthast, S; Pacheco-Salazar, D G (AVS 50th International Symposium, 2003)