Optical transitions and visible upconversion in Er3+ doped niobic tellurite glass

Abstract

Er 3+ doped Nb2O5–TeO2 (NT) glass suitable for developing optical fiber laser and amplifier has been fabricated and characterized. Intense and broad 1.53 μm infrared fluorescence and visible upconversion luminescence were observed under 975 nm diode laser and 798 nm laser excitation. For 1.53 μm emission band, the full width at half-maximum is 51 nm, the fluorescence lifetime is 2.6 ms, and the quantum efficiency is ∼100%. The maximum emission cross section is 8.52×10−21 cm2 at 1.532 μm, and is higher than the values in silicon and phosphate glasses. Under 798 nm excitation, efficient 531, 553, and 670 nm upconversion emissions are due to two-photon absorption processes. The “standardized” efficiency for the green upconversion light is 9.5×10−4, and this value is comparable to that reported for Er3+/Yb3+ codoped fluoride glasses. Intense visible upconversion fluorescence in Er3+ doped NT glass can be used in color display, undersea communication, and infrared sensor.

Femtosecond nonlinear optical properties of tellurite glasses

“…[10][11][12][13][14] These tellurite glasses are transparent in the visible, near, and middle infrared regions. In comparison with silica glasses, they present larger refraction index and smaller phonon energies ͑ϳ700 cm −1 ͒, comparable to germanate glasses.…”

Enhanced upconversion emission of three dimensionally ordered macroporous films Bi2Ti2O7:Er3+, Yb3+ with silica shell

“…All samples show three main peaks located at 525, 548 and 662 nm, which was attributed to the 2 H 11/ 2 -4 I 15/2 (525 nm), 4 S 3/2 -4 I 15/2 (548 nm), 4 F 9/2 -4 I 15/2 (662 nm) of Er 3 þ , respectively. The UC emission mechanism was investigated based on the relation between excitation light power and the emission intensity [21,22]. As shown in Fig.…”

Optical properties of Nd3+-doped and Er3+–Yb3+ codoped borotellurite glass for use in NIR lasers and fiber amplifiers

“…Currently, Er 3+ Yb 3+ -codoped glass has received considerable attention due to its potential applications in compact optical amplifiers and laser sources in the 1.55 µm band [9,10]. Yb 3+ is often used to enhance the absorption cross-section of Er 3+ at 980 nm and gives rise to 4 I 13/2 → 4 I 15/2 sensitized emission through the non-radiative energy transfer, Yb 3+ : 2 F 5/2 → Er 3+ : 4 I 11/2 .…”