Anomalous red luminescence of Sm3+ ions in Sm3+:LaKNaTaO5 single crystals

Abstract For the first time much more intense 4 G 5/2  →  6 H 9/2 transition than others 4 G 5/2 → 6 H J/2 transitions of the Sm 3+ -doped oxides have been observed. The Sm 3+ –doped LaKNaTaO 5 single crystals have been grown by the flux growth method. The emission and excitation spectra as well as decay profiles of the 4 G 5/2 luminescent level of the Sm 3+ ion have been measured. The decay curve has been fitted by the Inokuti-Hirayama energy transfer model which revealed that electric dipole-dipole interaction is responsible for the energy transfer processes in the Sm 3+ :LaKNaTaO 5 single crystals. The title phosphors may be potentially used as red phosphor for white light-emitting diodes.