Structural, optical, and spectroscopic properties of Er3+-doped TeO2–ZnO–ZnF2 glass-ceramics

Er3+-doped fluorotellurite thin film glasses with improved photoluminescence emission at 1.53 µm

“…Figure 4 shows the normalized reduced Raman spectra measured for the bulk glass, RTand AN-film glasses in the 250-900 cm -1 range. Raman spectra of similar bulk glasses have been previously reported and discussed [9,13,20,36], and thus here we compare them with the results obtained for the thin film glasses. Like in other tellurite glasses, the cut-off frequency of the optical phonon modes is ≈850 cm -1 , which reduces multiphonon relaxation of Er 3+ ions with respect to silica glasses (cut-off at ≈1100 cm -1 ) [6,8,9] and the spectra present the distinctive bands of tellurite glasses at 400-500 cm -1 (A), 600-700 cm -1 (B) and 700-800 cm -1 (C).…”

“…The target was prepared by the conventional meltquenching technique as described elsewhere [20]. Film deposition was carried out in a vacuum chamber evacuated to 10 -5 Pa and then filled with a dynamic oxygen flow of 10 Pa. [28].…”

“…In particular, fluorotellurite glasses belonging to the TeO 2 -ZnO-ZnF 2 system are promising RE hosts to be used in active optical applications, since they present high absorption cross-section [13,17], broad emission (≈ 150 nm) that covers S, C+L and U telecommunication bands when codoped with Er 3+ and Tm 3+ [18], and laser emission has been demonstrated in the case of Nd 3+ doped fluorotellurites [19]. Finally, we have recently reported the synthesis of fluorotellurite glass-ceramics, which opens a new range of applications [20].…”

Influence of Sb2O3 on tellurite based glasses for photonic applications

“…The other bands are distributed along the region 300-1000 cm -1 at around 367, 460, 663, 743, 851 and 922 cm -1 . Raman spectra of all the tellurite based glasses contain a huge band in the range 620-670 cm -1 [49][50][51][52]. …”

Investigation of upconversion luminescence in Yb3+/Tm3+/Ho3+ triply doped antimony-germanate glass and double-clad optical fiber

“…It is known that silicate and phosphate glasses posses high phonon energy (~1000e1200 cm À1 ) and thus a relatively high probability of nonradiative transition, which drives into low efficiency of energy transfer between the active dopants [25,26]. On the other hand, low-phonon oxide glasses such as tellurite (750 cm À1 ) or heavy metal oxide (HMO) glasses (600 cm À1 ) are characterized by high emission efficiency, but unfortunately they are usually weak mechanically [27,28]. Recently, antimony-based glasses have been presented and due to their low phonon energy (600 cm À1 ) and good thermal stability can be applied for fabrication of optical fibers [29e33, 36,38].…”