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Comparative analysis of luminescent properties of Nd3+/Yb3+ codoped optical fibers

In this article the luminescence properties of three different constructions of doble-clad optical fibers with multicores co-doped with Nd/Yb ions have been investigated. All fibers were made with thermally stable aluminosilicate glass. In each optical fiber, strong and wide emission in the 1μm range obtained by Nd3+ → Yb3+ energy transfer corresponding to the superposition of radiative transitions in two relaxation channels at 1062 nm (Nd3+: 4F3/2 → 4I11/2 ) and at 980 nm (Yb3+2: F5/2 → 2F7/2 ) was observed. Optimization of doping system, geometry and amount of cores in fabricated optical fibers shows the possibility of controlling the luminescence shape achieved directly from the end of fiber. Comparative analysis of shape of luminescence (λexc = 808 nm) obtained in fabricated optical fibers and amplified spontaneous emission were also discussed.