Judd-Ofelt and luminescence properties of Pr³⁺ doped ZnO-Gd<inf>2</inf>O<inf>3</inf>/GdF<inf>3</inf>-BaO-P<inf>2</inf>O<inf>3</inf> glasses for visible and NIR applications

Abstract

Two optimized glasses were prepared with composition 10ZnO-10Gd2O3–10BaO–69P2O3-1Pr2O3 (1ZGPr) and 10ZnO-10GdF3-10BaO–69P2O3-1Pr2O3 (2ZGPr) by melt-quenching technique and study their structural, optical, physical and emission properties. In the absorption spectra seven absorption bands were observed corresponding to transition from 3H4 state at 443 nm (3P2), 467 nm (3P1), 481 nm (3P0), 589 nm (1D2) in visible region and 1438 nm (3F4), 1527 nm (3F3) and 1940 nm (3F2) in NIR-region. The trend observed for JO-parameters for both 1ZGPr and 2ZGPr is Ω4>Ω6>Ω2. The 2ZGPr has higher value of Ω2 parameter value than 1ZGPr, showing more covalency and asymmetric environment around Pr3+-ions. Emission in NIR region exhibits three f-f transition located at 870 nm (3P1 → 1G4), 1040 nm (1D2 → 3F3, 3F4), and 1470 nm (1D2 → 1G4). The 3P0 → 3F2 (in visible) and 1D2 → 1G4 (in NIR region) transitions has higher branching ratio and stimulated emission cross section for 2ZGPr glass than 1ZGPr glass. The Full-width-half-maxima (FWHM) is analyzed for transition at 870 nm is 61 nm for 1ZGPr and 58 nm for 2ZGPr glass. The possibility of efficient signal-amplification in E-band, S-band due to affirmative emission of Pr3+-ions within broadband wavelength region in 1ZGPr and 2ZGPr glasses with transition at 1470 nm covering E−, S– C- and L-band. The assessed values of color-coordinates (x, y) are (0.57, 0.36) and (0.54, 0.36) for 1ZGPr and 2ZGPr respectively. Hence 2ZGPr glass has enough potential enough capability to emit bright red-laser at 640 nm.