RADIATIVE ENERGY TRANSFER AND "NON-NATURAL" EXCITATION IN THE QUANTUM EFFICIENCY DETERMINATION OF 1.55 µm Er3+ EMISSION IN SILICA FIBERS F. AUZEL et D. MEICHENINJ. Phys. IV France, 01 C7 (1991) C7-423DOI: https://doi.org/10.1051/jp4:19917111
