Neodymium-to-erbium nonradiative energy transfer and fast initial fluorescence decay of the ^4F_3/2 state of neodymium in garnet crystals

Abstract

Two measurements were performed of the fast initial fluorescence decay of the 4F3/2 state of Nd3+, following pulsed excitation of the ion in two garnet crystals, (i) Nd(1%), Er(15%), Cr(1%):YAG and (ii) Nd(1.5%), Er(20%):YSGG. The nature of the interaction between Nd3+ and Er3+ ions is analyzed with a Monte Carlo model for the nonradiative energy transfer from Nd to Er. Our measurements and the Monte Carlo analysis corroborate the presence of a submicrosecond fluorescence decay transient and the reported nature of the interaction that drives the energy transfer, i.e., a mixture of electrostatic interactions (dipole–dipole, dipole–quadrupole, and quadrupole–quadrupole) and an exchange interaction.