Spectral analysis of Er3+-, Er3+/Yb3+- and Er3+/Tm3+/Yb3+-doped TeO2–ZnO–WO3–TiO2–Na2O glasses

Abstract

In this paper, we present the spectroscopic properties ofEr3+-,Er3+/Yb3+- andEr3+/Tm3+/Yb3+-dopednovel tellurite glasses. From the measured absorption spectra, Judd–Ofelt (JO) intensity parameters(Ω2,Ω4 andΩ6) have beenevaluated for the Er3+-doped glass. With 980 nm excitation three strong upconversionemission bands centered at 505, 520 and 630 nm were observed for bothEr3+- andEr3+/Yb3+-codoped glasses and the characteristic near-infrared emission bands were spectrally centered at1.535 µm. Thenear-infrared spectra of Er3+- and Er3+/Yb3+-doped glasses have shown full width at half-maxima (FWHM) around 100 nm and 120 nmfor the erbium transition, respectively. The measured maximum decay times of the transition (at wavelength1.535 µm) are about7.24 ms and 7.68 ms for 1.0Er3+ and 1.0Er3+/ 2Yb3+ (mol%)-codoped glasses, respectively. The maximum stimulated emission cross sectionsfor the transition of Er3+ and Er3+/Yb3+ are 8.64 × 10−21 and 6.78 × 10−21 cm2.From 1Er3+/ 1Tm3+/ 2Yb3+ (mol%)-codoped glass, broad near-infrared emission bands centered at 1510 nm () and 1637 nm () with full width at half-maxima (FWHM) around 52 nm and 60 nm, respectively, wereobserved. These glasses with broad near-infrared emissions should have potentialapplications in tunable lasers and broadband optical amplification at low-losstelecommunication windows