Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE
Optimization of Pr3+-doped fluoride fiber amplifiers and substantial performance improvement with a pump reflecting mirror
Mala Krishnan, Steven P. Bastien, Harish R. D. Sunak
Abstract
We report on optimized performance of Pr3+ doped fluoride fiber amplifiers (PDFA) using a comprehensive spatial and spectral computer model. We show the correspondence between results that were experimentally determined and those obtained using our model. Waveguide parameters for these amplifiers have been optimized for low and moderate values of relative refractive index difference. A cut-off wavelength of 750 nm gives maximum gain for NA equals 0.1 and 0.2. Particular emphasis is given to a comparison of the PDFA's performance with and without a Bragg reflecting pump mirror etched at the output end of the fiber. A pump reflecting mirror gives higher gain at smaller amplifier lengths (approximately equals 1/3) in both, the small and large signal regimes. We also report on the quantum conversion efficiencies (QCE) of PDFA. For the same length of fiber and a 0 dBm input signal, PDFA with a pump reflecting mirror has a QCE about twice that of a PDFA without a pump reflecting mirror at its output end.