Investigation of Li2O–Gd2O3–MO–B2O3–Nd2O3 (MO=Ba/Bi) glasses for laser applications by Judd–Oflet (J–O) theory

Abstract

In this work, we synthesize Li2O–Gd2O3-MO-B2O3–Nd2O3 glasses (where MO = Ba/Bi) by melt-quenching technique for laser applications; characterize their physical properties, absorption and luminescence spectra; and determine their decay time and Judd-Oflet (J-O) parameters. We confirm the glass phase of the samples by XRD pattern and obtain the J-O parameters for Nd3+ in the glasses from the absorption and photoluminescence emission spectra, while measuring the intensity of the electric dipole transitions and oscillator strengths from absorption spectra and the radiative parameters from photoluminescence emission spectra. We also determine some key parameters of the laser materials, such as radiative decay time, quantum efficiency and stimulated emission cross section. The lifetime decreases with increasing Nd3+ concentration that is indicative of energy transfer between Nd3+ ions. We also demonstrate that the physical properties and absorption spectra are independent of the gadolinium ions (Gd2O3), while the luminescence properties are functions of the Gd2O3 due to the efficient energy transfer from the Gd3+ ions to the incorporated activator (Nd3+). These results suggest that the 50Li2O-15Gd2O3–5Bi2O3-28.5B2O3-1.5Nd2O3 glass is useful for laser applications at 577-nm excitation and at 1.07-μm emission.