Assessment of optical and fluorescence aspects of Er3+-doped multicomponent B2O3 glasses as active media for 1.532 μm near-infrared optical amplifiers

Abstract

Current work principally provides an idea on controlling the Er3+: NIR (near-infrared) emission characteristics by changing a glass constituent and finding a suitable glass host favorable to design a novel C-optical band (1.53–1.565 μm) amplifier. By melting and rapid quench route, six transparent Er3+ (1 mol%)-doped B2O3-rich glasses having different single and mixed alkali ions were fabricated, and optical and fluorescence (visible and NIR) traits including Er3+ ion upper-levels 4S3/2 and 4I13/2 decay dynamics were inspected for such samples. At 1.4–1.65 μm wavelength range, an intense and wide NIR luminescence band centered at 1.532 μm (Er3+: 4I13/2 → 4I15/2 transition) has been obtained by a 980 nm laser diode pumping (4I15/2 → 4I11/2). NIR fluorescence Δλeff (effective bandwidth) varied depending on added single or mixed alkali ions, and a maximum Δλeff ∼74.66 nm was acquired for Er3+: Li ions constituting glass. For the 4I13/2 → 4I15/2 transition, σemi (stimulated emission cross-section) was evaluated using both Füchtbauer–Ladenburg and McCumber's theories. In all glasses, comparably, higher gain bandwidth (= 5.384 × 10−26 cm3) and peak σemiM (= 1.692 × 10−20 cm2) values have been attained for 4I13/2 → 4I15/2 transition in Li ions containing sample, and also this glass possesses the largest σabs (absorption cross-section) (= 1.459 × 10−20 cm2) for 4I15/2 → 4I13/2 transition. Further, at distinctive P (population inversion) values, gain spectra were computed, and all samples show C-optical band amplification beginning from P = 50%. All analyzed NIR fluorescence results indicate that Li ions having glass could be a potential gain medium for fiber amplifiers.

Keywords

• B2O3 glasses
• Er3+
• Judd-Ofelt analysis
• Fluorescence characteristics
• CIE color coordinates
• C-optical band amplifier