Wideband optical amplifier based on Tm:Er:Yb:Ho co-doped germanate glass

In this paper, an innovative Tm:Er:Yb:Ho co-doped germanate fiber glass amplifier, pumped at λ
_p
= 980 nm, is designed and optimized, to obtain a wideband/three band amplification in the wavelength range λ = 1.4 - 2.1 μm. A preliminary investigation has shown the dependence of the optical gain on the dopant concentrations, the fiber length and the pump power. To obtain a suitable three-band gain, a Particle Swarm Optimization (PSO) algorithm is applied in order to perform a global optimization.