Green fluorescence of terbium ions in lithium fluoroborate glasses for fibre lasers and display devices

Abstract

In this paper, for the first time, the visible fluorescence properties, resonance energy transfer mechanism responsible for non-radiative decay rates of 5D4 → 7F5 transition and also quenching of fluorescence intensity of the 5D3 →7F5 transition of various concentrations of Tb3+ ions in LBZLFB glasses are reported. Optical absorption, fluorescence spectra and quantum efficiencies are measured and analysed. Green fluorescence related to 5D4 → 7F5 (548 nm) transition is registered under excitation of 378 nm of Tb3+ ions. Based on excitation and fluorescence measurements, several spectroscopic parameters for Tb3+ ions are examined as a function of concentration by Judd'COfelt theory to judge the suitability of studied glasses for display devices and fibre lasers.