Spectroscopy of Tm3+-doped tellurite glasses for 1470 nm fiber amplifier

Abstract

Optical properties and frequency upconversion fluorescence in a Tm3+ -doped alkali niobium tellurite glassThree thulium doped tellurite glass compositions have been investigated. The 1470 nm transition is radiative in these tellurite glasses and the radiative lifetimes are in the range of 350 to 470 s. The 1470 nm fluorescence is broad with a full width at half maximum of 105 nm. Fibers have been drawn from these glasses with a loss of 0.7 dB/m at 1300 nm. A fiber with an OH fundamental absorption of 200 dB/m at 2.99 m has an OH first overtone absorption of 0.3 dB/m at 1480 nm. The overlap between the thulium ion 1470 nm emission and the hydroxyl absorption depends on glass composition. Tellurite glasses can accept large concentrations of Tm 3ϩ ions and, as long as the hydroxyl level can be kept low, the effect of concentration quenching can be minimized. Tm 3ϩ -doped tellurite glasses represent a viable alternative for the next generation of active components for S-band optical amplifiers. It can be pumped at 795 nm with an absorption of ϳ38 dB/km/ppm and codoped with Ho 3ϩ to avoid self-termination of the 1470 nm transition. It can also be pumped at 1212 nm as efficiently as at 795 nm, but diodes are not yet available at this wavelength. Using available pump wavelengths of 1064 nm and 1047 nm will require fiber lengths 15 times longer than pumping at 1212 nm.

1.48 and 1.84 μm thulium emissions in monoclinic KGd(WO4)2 single crystals

“…4 we present the temperature evolution from 10 K to RT of the 1.84 m emission. We observed five peaks at 1.770, 1.791, 1.808, 1.842 and 1.869 m at 10 K, which correspond to the electronic transitions 3 F 4 (0Ј)→ 3 H 6 (0), 3 F 4 (0Ј)→ 3 H 6 (1), 3 F 4 (0Ј)→ 3 H 6 (3), 3 F 4 (0Ј)→ 3 H 6 (7) and 3 F 4 (0Ј)→ 3 H 6 (9), respectively. These Stark sublevels of the ground state 3 H 6 are located at 0, 69, 119, 223 and 300 cm Ϫ1 , respectively.…”

“…We labeled the n Stark levels, increasing from 0 to n in energy, nЈ for the upper level and n for the lower level. At 10 K the spectrum shows eight peaks at 1.440, 1.450, 1.452, 1.457, 1.482, 1.500, 1.502 and 1.508 m, which correspond to the electronic transitions 3 H 4 (0Ј)→ 3 F 4 (0), 3 creased when the temperature increased. This is due to the thermal population of the sublevels, so at 100 K some new peaks appeared that corresponded to the electronic transitions 3 Fig.…”

“…This transition is self-terminating because the lifetime of the 3 F 4 terminal level is longer than that of the 3 H 4 emitting level. 2,3 This creates a detrimental bottlenecking effect because it is difficult to achieve the population inversion between the 3 H 4 and 3 F 4 states without depopulating the lower state. On the other hand, this transition has two competitive transitions, the 3 H 4 → 3 H 6 transition, around 800 nm, and the 3 H 4 → 3 H 5 transition, around 2.3 m. Both situations are complicating the realization of a highly efficient optical amplification at 1.5 m. In 1983, Antipenko et al 4 Bagaev et al 7 in 2000 at RT.…”

Optical properties and frequency upconversion fluorescence in a Tm3+ -doped alkali niobium tellurite glass

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] An important characteristic of these materials is the relatively low cutoff phonon energy compared with other oxide glasses such as silicate or phosphate glasses. This property has motivated a large number of experiments dedicated to the study of the optical properties of TG doped with RE ions, and thus these glasses are revealed to be strong candidates for uses in photonic devices.…”

“…Much attention was given particularly to Tm 3ϩ -doped TG because of the possibility of producing blue laser radiation pumping in the infrared and optical amplification. [9][10][11] In previous works, TG were chosen as a host to study energy transfer processes between RE ions in doubly and triply doped samples. 4,[12][13][14][15][16] In this work, we present spectroscopic properties of Tm 3ϩ ion in alkali niobium tellurite glasses.…”