Structure and Luminescence Properties of Transparent Germanate Glass-Ceramics Co-Doped with Ni(2+)/Er(3+) for Near-Infrared Optical Fiber Application

An investigation of the structural and luminescent properties of the transparent germanate glass-ceramics co-doped with Ni(2+)/Er(3+) for near-infrared optical fiber applications was presented. Modification of germanate glasses with 10–20 ZnO (mol.%) was focused to propose the additional heat treatment process controlled at 650 °C to obtain transparent glass-ceramics. The formation of 11 nm ZnGa(2)O(4) nanocrystals was confirmed by the X-ray diffraction (XRD) method. It followed the glass network changes analyzed in detail (MIR—Mid Infrared spectroscopy) with an increasing heating time of precursor glass. The broadband 1000–1650 nm luminescence (λ(exc) = 808 nm) was obtained as a result of Ni(2+): (3)T(2)((3)F) → (3)A(2)((3)F) octahedral Ni(2+) ions and Er(3+): (4)I(13/2) → (4)I(15/2) radiative transitions and energy transfer from Ni(2+) to Er(3+) with the efficiency of 19%. Elaborated glass–nanocrystalline material is a very promising candidate for use as a core of broadband luminescence optical fibers.