Upconversion channels in Er3+:ZBLALiP fluoride glass microspheresD. G. O'Shea, J. M. Ward, B. J. Shortt, M. Mortier, P. Féron and S. Nic ChormaicEur. Phys. J. Appl. Phys., 40 2 (2007) 181-188DOI: https://doi.org/10.1051/epjap:2007148
