Dy 3+-doped Ge–Ga–Sb–Se glasses for 1.3 μm optical fiber amplifiers

Abstract

The Ge x Ga 5Sb 5Se (90− x) glasses, where x = 20, 22.5, 25, 27.5, and 30, all doped with 1000 ppm wt Dy 3+ are prepared. Thermal stabilities, optical properties and 1.3 μm emission properties of the glasses are investigated. Strong fluorescence centered at 1.34 μm with a bandwidth of 92 nm is observed. Three phenomenological intensity parameters are obtained, Ω 2 = 11.61 × 10 −20, Ω 4 = 2.79 × 10 −20 and Ω 6 = 1.11 × 10 −20 cm 2 by a Judd–Ofelt analysis. A new method estimating lifetime of overlapping energy levels is proposed. Lifetimes of 530 μs are observed for the 1.3 μm transition and the corresponding efficiency is 37.1% according to the new method.