Solving Rate Equations Including Background Losses Applicable to Threshold Pumped Fiber Lasers with Three-Energy-Level Dopants

Abstract

An analytical expression of the threshold pump power of the fiber laser with three-energy-level dopants has been obtained from rate equations including loss coefficients of the pump and laser radiations. And the rate equations describing the threshold pumped fiber lasers have been analytically solved following the derivation of the implicit expression specifying the pump variation along the fiber and expressions of the position dependent population densities on the three energy levels in terms of the pump variation.