Investigation of modifier effect on the spectroscopic properties of Sm3+ ions in binary boro-bismuth glasses

Trivalent samarium (Sm3+)-doped boro-bismuth glass systems are prepared using the well-known melt quenching technique and studied their physical and spectroscopic properties. Theoretical optical basicity of the glasses are evaluated using the glass compositions. The optical absorption spectra are used to predict the optical band gap and bonding parameters of glasses. The ultra violet (UV) cutoff wavelength is increasing towards the higher wavelength side with increase in bismuth concentration. Judd-Ofelt parameters are obtained from absorption spectrum and are inturn used to estimate radiative properties for various excited states of the Sm3+ ions in born-bismuth glasses. Luminescence decay curves of the (4)G(5/2) level in the Sm3+-doped boro-bismuth glasses are measured under 402 nm excitation. The decay times exhibit single exponential nature for lower concentrations (<= 0.1 mol%) and tends towards non-exponential with increase in Sm3+ concentrations (>= 0.5 mol %). The non-exponential decay curves of higher Sm3+-doped glasses are fitted to the Inokuti-Hiriyama model to know the nature of interaction for energy transfer between the Sm3+ ions. The chromaticity color coordinates for present glass systems are also evaluated and found that the luminescence color falls in the reddish-orange region.