Spectroscopic study of Sm:Ce ions co-doped in barium fluoroborate glass

The spectroscopic properties of Sm, Ce and Sm:Ce doped in barium fluoroborate glasses are reported and discussed. Under 266 nm and 355 nm excitations, Ce3+ ion emit broad blue emission due to 5d–4f transition however Sm doped glasses yield usual orange-red emissions due to 4f–4f transitions with modified intensity. Luminescence spectrum of Sm:Ce codoped glass sample reveals strong energy transfer from Ce3+ to Sm3+ ions. In Sm:Ce doped sample, emission intensities of Sm3+ as well as of Ce3+ bands are reduced considerably with 355 nm excitations, while intensities of Sm3+ bands are enhanced under 266 nm excitations. The reduction in emission intensity on 355 nm excitations is verified with the formation of Ce4+ and Sm2+ ions while in case of 266 nm excitation, energy transfer from Ce4+–O charge transfer state to Sm3+ ion is expected to dominate. Formation of Sm2+ on the cost of Sm3+ ions was supported by luminescence dynamics measurements.