Optical Properties of Rare-Earth Ions Doped Lithium Boro Tellurite Glasses

摘要

The optical properties of Sm~(3+), Dy~(3+) and Ho~(3+): 20TeO_2-74B_2O_3-5Li_2O glasses have been investigated from the measurement of absorption and emission spectral profiles. Besides the optical analysis, we have been also studied the physical and other related properties of these optical materials. For Sm~(3+) doped glass, a prominent an intense orange-reddish emissions ~4G_(5/2) → ~6H_(7/2 & 9/2) at an excitation level 401nm, and a bluish yellow emission bands ~4F_(9/2) → ~6H_(15/2 & 13/2) at λ_(exc) = 450nm for Dy~(3+) have been observed. Similarly, Ho~(3+) doped glass, a prominent and strong red emission at 643 nm (~5F_5→~5I_8) has been observed when excited at 399 nm. The up-conversion emission spectrum has revealed three up-conversion emissions at wavelengths of 425, 472 and 525 nm, upon excitation at 643 nm. The up-conversion emissions have been explained in terms of a three-photon absorption process, through an energy level diagram. From these results, we understand that the holmium glass has a good potential application as a red luminescent optical glass and also as a green up-converting luminescent material. Eventually, further studies are underway to study up-conversion phenomena of Sm~(3+)and Dy~(3+) doped Lithium Boro- Tellurite glasses.