Study of luminescence properties of Er³⁺-ions in new tellurite glasses

The effects of concentration of Er³⁺ ions in tellurite glasses on the decay time, spectral width and weighted spectral peak are studied. A broad emission spectrum of width 121 nm peaked at wavelength of 1.5 μm is obtained in 2.5 mol% Er doped glasses. The maximum decay time of ⁴I_13/2→⁴I_15/2 transition (at wavelength 1.5 μm) is about 4.5 ms for 1.0 mol% Er doped glasses. Strong green and red upconversion emission at emission 550 nm (⁴S _3/2→⁴I_15/2) and 670 nm (⁴F _9/2→⁴I_15/2) are observed from Er ³⁺-doped tellurite glasses upon continuous wave excitation at 975 nm. It is found that the upconversion efficiency goes up with the increasing concentration of the Er³⁺ ions.