Optimum design of radiation-hardened and high power Er3+-Yb3+-codoped fiber amplifiers by means of particle swarm approach

International audience; In this paper, the design of a rare earth-doped claddingpumped fiber amplifiers is carried out by means of a homemade computer code based on particle swarm optimization (PSO) and rate equation model. In particular, taking into account experimental results, a full investigation of radiation-hardened double-cladding Er3+-Yb3+-doped fiber amplifiers (EYDFAs) has been performed. A detailed rate equation model including the first and secondary energy transfer between Yb3+ and Er3+, the presence of Er3+ and Yb3+ clusters, the amplified spontaneous emission (ASE) and the most relevant Er3+ upconversion and cross relaxation mechanism is considered. The obtained results highlight that the developed PSO algorithm is an efficient and reliable tool for performing the optimum design of radiation-hardened and high-power EYDFAs.