Optical spectroscopy and luminescence properties of a Tm3+-doped LiKB4O7 glass

Abstract Spectroscopic properties of the Tm-doped borate glass with LiKB 4 O 7 (0.5Li 2 O–0.5K 2 O–2B 2 O 3 ) basic composition are investigated and analysed using optical absorption and photoluminescence (excitation, emission, decay kinetics) experimental techniques as well as Judd–Ofelt analysis. Optical absorption spectra exhibit absorption bands related with transitions of Tm 3+ ions. The theoretical and experimental oscillator strengths for observed absorption transitions as well as Judd–Ofelt intensity parameters (Ω 2 , Ω 4 , Ω 6 ) have been calculated. Photoluminescence spectra reveal a lot of emission bands in the visible and infrared spectral ranges related with 4 f – 4 f transitions of Tm 3+ ions. Luminescence decay kinetics of several excited states was detailed investigated and analysed. Radiative properties such as radiative transition probabilities ( A rad ), luminescence branching ratios ( β ), radiative lifetimes ( τ rad ), quantum efficiency ( η ), and stimulated emission cross-section ( σ em ) have been estimated. The obtained results show that the investigated LiKB 4 O 7 :Tm glass belongs to perspective luminescent and laser materials in the visible and infrared spectral ranges.