Synthesis and optical spectroscopy of borate glasses, doped with terbium and dysprosium

Abstract

The high optical quality glasses with CaB4O7:Tb, LiCaBO3:Tb, CaB4O7:Dy, and LiCaBO3:Dy compositions containing 0.5 and 1.0 mol. % Tb2O3 and Dy2O3 have been obtained. By electron paramagnetic resonance (EPR) and optical spectroscopy it was shown that the Tb and Dy impurities are incorporated in the CaB4O7 and LiCaBO3 glass network as Tb3+ (4f8, 7F6) and Dy3+ (4f9, 6H15/2) ions, exclusively. All observed f – f transitions of Tb3+ and Dy3+centres in optical absorption, luminescence excitation and emission spectra have been identified. Luminescence kinetic shows single exponential decay for Tb3+ and Dy3+ centres in the CaB4O7 and LiCaBO3 glasses. Lifetimes for main emitting levels of Tb3+ and Dy3+ centres in all investigated glasses were determined at T = 300 K. Spectroscopy shows that obtained glasses are promising luminescent materials.