Broadband mid-infrared 2.0 μm and 4.1 μm emission in Ho3+/Yb3+ co-doped tellurite-germanate glasses

Spectroscopic Properties of Erbium-Doped Oxyfluoride Phospho-Tellurite Glass and Transparent Glass-Ceramic Containing BaF2 Nanocrystals

“…Figure 8 shows normalized Raman spectra of glasses doped with various erbium trifluoride content in the 1300–500 cm −1 range. The Raman spectra of all samples (Figure 8) have bands that are attributed to the bond vibration occurring in the tellurium (300–800 cm −1 ) [81,82,83,84,85] as well as phosphate (900–1300 cm −1 ) [86,87,88,89,90] glass network. Additionally for Raman spectra, it was necessary to deconvolution selected spectra for better understanding the structure of glasses (Figure 9, Figure 10 and Figure 11).…”

“…The band at around 669/653/645 cm −1 can be assigned to the stretching variation of Te–O, F bonds in [Te(O, F) 4 ] units [83]. The band at around 714–704 cm −1 is assigned to the Te(O, F) 4 tbp units [84]. The band located at 780 cm −1 can be ascribed to Te–O − stretching vibration in [TeO 3 ] trigonal pyramids or symmetric stretching vibration in [TeO 3+1 ] units [85].…”

Investigation of the TeO2/GeO2 Ratio on the Spectroscopic Properties of Eu3+-Doped Oxide Glasses for Optical Fiber Application

“…They are related to the host matrix’s phonon energy, the solubility of lanthanides ions, and the ligand field around rare-earth ions. Reducing the host glass phonon is a condition to achieve high-efficiency mid-infrared luminescence [ 6 ]. Among glass hosts, heavy metal oxides (HMO) glasses and especially the tellurite and germanate glasses have drawn growing interest as alternative hosts for mid-infrared emitting optical centers [ 7 ].…”

Intense emission at 2.9 μm from Yb3+/Ho3+ co‐doped TeO2–Ga2O3–ZnO tellurite glasses

“…To achieve high efficient mid‐infrared luminescence, the choice of glass matrix with low phonon energy and enough robust is very important, because non‐radiative transitions can significantly reduce the luminescence efficiency 1 . Based on the above requirements, the high‐efficiency emission of Ho 3+ : 2.9 μm fluorescence is mainly concentrated in fluoride glass and sulfide glass matrix, but their mechanical properties and chemical stability are poor 7 . Tellurite glass possesses relatively low phonon energy (~760 cm −1 ) and a large transmission window 1,8 .…”

“…1 Based on the above requirements, the high-efficiency emission of Ho 3+ : 2.9 μm fluorescence is mainly concentrated in fluoride glass and sulfide glass matrix, but their mechanical properties and chemical stability are poor. 7 Tellurite glass possesses relatively low phonon energy (~760 cm −1 ) and a large transmission window. 1,8 Meanwhile, it has better mechanical properties and chemical stability than fluoride and sulfide glasses.…”