Energy-Transfer Processes Among Non-Homogeneously Distributed Rare-Earth Ions and Impact on Amplification and Lasing

Abstract

Energy-transfer processes such as energy-transfer upconversion are often detrimental to the performance of rare-earth-doped amplifiers and lasers on the typical luminescence transitions in the near-infrared spectral region between 1-2 μm. In order to quantify the influence of these interionic processes on amplification and lasing, not only luminescence decay curves have to be measured, but also the population dynamics of the electronic level scheme need to be modeled. The usually encountered non-homogeneous ion distributions complicate the situation. Here we present a stochastic model of energy-transfer processes that takes a statistical ion distribution into account. The influence of energy-transfer upconversion and cross-relaxation on amplification and lasing on the 1.06 μm transition in Nd3+, the 1.53 μm transition in Er3+, or the 1.84 μm transition in Tm3+ under these conditions is investigated.