Erbium-doped hole-assisted optical fiber amplifier: design and optimization

An erbium-doped hole-assisted optical fiber amplifier, to be employed in the third band of the optical communications, is designed and optimized via a tailor made computer code. The finite element method is used for the electromagnetic investigation of the microstructured fiber section. The simulation model takes into account all the rare earth physical phenomena, i.e., the pump and signal propagation, the amplified spontaneous emission, the secondary transitions pertaining to the ion-ion interactions, and so on. The device feasibility is tested via a number of simulations, realistically performed by taking into account the actual parameters pertaining to the dispersion of the germania/silica glass, the erbium emission and absorption cross sections, the propagation losses. By simulation, in the small signal operation, a gain close to 42.8 dB is demonstrated for a fiber 13-m long, using a pump power of 50 mW at the signal wavelength /spl lambda//sub s/=1536 nm, the pump and the signal being copropagating.