Luminescence properties of Sm3+ ions doped heavy metal oxide tellurite-tungstate-antimonate glasses

The trivalent Sm3+ ion doped tellurium-antimony-tungsten oxides based glasses were prepared by conventional melt quenching and pressing method. Spectroscopic characterizations such as optical absorption, photoluminescence and decay profile measurements were performed on the glasses. Judd-Ofelt theory is used to evaluate the oscillator strengths and the three phenomenological intensity parameters (Omega(lambda), lambda = 2, 4, 6) of the glasses. The photoluminescence spectra recorded under 479 nm excitation exhibited the emission bands at 562, 598, 645 and 708 nm corresponding to the transitions (4)G(5/2) -> H-6(J) (J = 5/2, 7/2, 9/2, 11/2) respectively. Using J-O parameters (Omega(lambda)) various important radiative parameters viz., transition probabilities, emission cross-sections, branching ratios of various emission bands were evaluated. Decay profiles were recorded to find the lifetime of the (4)G(5/2) excited level and the obtained life time values are observed to decrease with an increase of Sm3+ ion concentration; such decrease is attributed due to clustering of Sm3+ ions which may cause luminescence quenching.