Thermal, Optical, and IR-Emission Properties of Extremely Low Hydroxyl TeO2-WO3-Bi2O3-La2O3-xEr2O3 Glasses for Mid-Infrared Photonics

A series of glass samples the tungsten–tellurite system TeO2-WO3-Bi2O3-(4-x) La2O3-xEr2O3, x = 0; 0.4; 0.5; 0.7; 1.2; 2; 4 mol%, CEr 0 - 15 × 1020 cm?3 were synthesized from high-purity oxides in an oxygen flow inside a specialized sealed reactor. In all series, extremely low content hydroxyl groups was achieved (~n 1016 cm?3, more than orders magnitude lower concentration erbium ions), which guarantees minimal effects on luminescence properties Er3+. The glasses are resistant to crystallization up mol% Er2O3, and transition temperatures do not depend oxide when introduced by replacing lanthanum oxide. Thin 0.2 mm plates have high transmittance at level 20% 4.7–5.3 µm range, absorption bands about 2.3, 3, 4.4 µm, typical for ordinary tellurite samples, indistinguishable. introduction led insignificant change refractive index. Er2O3-concentration dependences intensities lifetimes near wavelengths 1.53 2.75 ?m found 4I13/2–4I15/2 4I11/2–4I13/2 /transitions Er3+ ion. data obtained necessary development mid-infrared photonics; particular, design Er3+-doped fiber lasers.