Studies on near infrared emission of Yb3+ ions in a SeO2 based glass system

SeO2 based glasses of the composition 39 PbO–(60-x) B2O3– xSeO2:1.0 Yb2O3 (with 10 ≤ x ≤ 50) was synthesized. Analysis of the results of structural studies of the samples revealed that the glass network consists of [SeO4]2− and [SeO3]2− units; the studies further indicated an increasing fraction of [SeO3]2− units and decreasing concentration of [SeO4]2− groups with increase of SeO2 content. Optical Absorption (OA) and photoluminescence (PL) spectra have exhibited bands due to 2F7/2 → 2F5/2 and 2F5/2 → 2F7/2 transitions, respectively. Evaluated absorption and emission cross-sections and lifetime of the excited state of Yb3+ ions exhibited an increase with increase of SeO2 content. Results of PL studies indicated nearly fourfold increase of PL output with increase of SeO2 content up to 50%. Such increase is attributed to the increased concentration of isolated [SeO3]2- pyramidal groups. Overall, the rise of SeO2 content in Yb3+ doped PbO–B2O3–SeO2 glass system facilitated the increase of PL emission of Yb3+ ions largely.