Spectroscopic and Thermal-Luminescence Behavior of Rare-Earth/Actinide-Doped Glasses for Advanced Optoelectronic Applications

Abstract

A sample of Er3+ doped fluorochloride glass was prepared by incorporating chlorine (Cl¯) into a fluoride glass (ZBLAN) using the conventional melt quenching technique. The research investigated the chemical stability, thermal stability, and fluorescent properties of the glass by varying the Cl¯ concentration. It was observed that increasing the Cl¯ concentration enhances the luminescent intensity in the infrared region. The strongest luminescent intensity was achieved at a Cl¯ concentration of 15 mol%. Similarly, the study compared the effects of different Er3+ concentrations on the luminescent properties of the fluorochloride glass, identifying 1 mol% Er3+ as the optimal doping concentration. Consequently, the glass composition is denoted as ZBLAN:15Cl, 1Er. Experimental analyses including X-ray diffraction (XRD), absorption spectrum, near-infrared spectrum (NIR), and mid-infrared spectrum (MIR) were conducted to characterize the Er3+ doped fluorochloride glass. The energy level diagram of Er3+ and the infrared luminescence of the sample were thoroughly analyzed, focusing on the excitation at 980 nm. Judd-Ofelt parameters were computed to understand the luminescent behavior. It was observed that Ω2 initially increased and then decreased with varying Cl¯ content in the glass matrix, whereas Ω4 and Ω6 remained relatively stable across different compositions. This variability in Ω2 suggests a change in the crystal field environment around the Er3+ ions due to the introduction of Cl¯. In Er3+ doped fluoride glass, the addition of Cl¯significantly enhances the mid-infrared luminescence intensity. The calculated Judd-Ofelt theoretical parameters indicate that Cl¯ introduction enhances the covalency of the coordination bond with Er3+, thereby reducing local symmetry and boosting the luminescent properties of the fluoride glass. This research on rare earth ion-doped fluorochloride glass provides a theoretical foundation for improving luminescent characteristics and offers valuable insights for the development and application of similar mid-infrared luminescent materials.