Title :
Concentration-dependent upconversion in Er/sup 3+/-doped fiber amplifiers: Experiments and modeling
Author :
Blixt, P. ; Nilsson, J. ; Carlnäs, T. ; Jaskorzynska, B.
Author_Institution :
Dept. of Phys. II, R. Inst. of Technol., Stockholm, Sweden
Abstract :
Eight different fibers were studied to examine upconversion as a function of erbium concentration below 1000 ppm by weight. These experiments and a computer model of two-particle upconversion made it possible to estimate the upconversion coefficient used in a rate-equation model. A strong correlation was found between amplification reduction and parasitic upconversion in fibers with both Ge- and Ge/Al/P-cores when the erbium-doping concentration is in the range 70-840 ppm by weight. When plotting maximum amplification versus the 980 luminescence on a logarithmic scale, the slope was approximately -2 irrespective of the host material. The validity of the assumed two-particle upconversion model up to 4 mW of pump power is shown.<>
Keywords :
aluminium compounds; erbium; fibre lasers; germanium compounds; optical pumping; phosphorus compounds; population inversion; 4 MW; Er concentration; Er/sup 3+/-doped fiber amplifiers; GeO/sub 2/-Al/sub 2/O/sub 3/-P/sub 2/O/sub 5/:Er/sup 3+/; GeO/sub 2/:Er/sup 3+/; amplification reduction; computer model; concentration dependent upconversion; host material; luminescence; maximum amplification; parasitic upconversion; pump power; rate-equation model; two-particle upconversion; upconversion coefficient; Artificial intelligence; Doped fiber amplifiers; Erbium; Erbium-doped fiber amplifier; Fluorescence; Optical fiber cables; Photonics; Silicon compounds; Stationary state; Telecommunications;
Journal_Title :
Photonics Technology Letters, IEEE
