Mid-infrared luminescence in HMO glass co-doped with Ho3+/Yb3+ ions

Abstract

In this work, heavy metal oxide glasses based on Bi 2 O 3 –GeO 2 –Ga 2 O 3 –Na 2 O system have been synthesized under a low vacuum conditions. This procedure reduced absorption band at 3 μm due to OH - ions concentration decrease to 50 ppm. Glass has been characterized by low phonon energy (724 cm -1 ), low absorption coefficient in the infrared region (1.0 cm -1 ) and good mechanical and chemical properties. In order to obtain luminescence in the MIR region, holmium and ytterbium ions have been incorporated into the glass matrix. Emission intensity analysis at 2.85 μm associated with the radiative transition between excited levels 5 I 6 → 5 I 7 in holmium ions under 980 nm laser diode excitation have been investigated. Obtained results allowed to determine the optimal concentration of co-dopants for maximum luminescence intensity. This demonstrate that developed heavy metal oxide glass is an attractive material for mid-infrared applications.