Fluorescence Full Width At Half Maximum Research Articles

Erbium-doped fluorotellurite titanate glasses for near infrared broadband amplifiers

A novel Er3+-doped fluorotellurite titanate glasses with the basic molar composition 75TeO2- 5Nb2O5- 5Bi2O3- 5TiO2- 10PbF2, 75TeO2- 5Nb2O5- 5Bi2O3- 5TiO2- 10PbF2- 10000 ppm Er2O3 and 75TeO2- 5Nb2O5- 5Bi2O3- 5TiO2- 10PbF2- 20000 ppm Er2O3 are explored with respect to possible applications as optical amplifiers. Their thermal and optical features were determined using differential scanning calorimetric (DSC), and UV–Vis–NIR spectroscopy, respectively. The glasses transition temperature Tg, factor against crystallization S, optical energy gap and quantum efficiency were determined. Judd-Oflet parameters Ωt (t = 2, 4, 6), branching ratio, β, fluorescence full width at half maximum (FWHM) of NIR emission, and life time τ, of I13/2 level have been evaluated. The glasses were characterized by a higher values of FWHM of NIR emission at 1.53 μm under excitation by wavelength 980 nm with respect to other glasses system doped by single Er3+ions. In the future these glasses can be fabricated as broadband fiber amplifier for the optical communication devices. The glasses studied glasses exhibit green emission under excitation wavelength of 445 nm.

Effect of SiO2 on the thermal stability and spectroscopic properties of Er3+-doped tellurite glasses

Er3+-doped tellurite glass (TeO2-ZnO-Na2O) prepared using the conventional melt-quenching method is modified by introducing the SiO2, and its effects on the thermal stability of glass host and the 1.53 μm band spectroscopic properties of Er3+ are investigated by measuring the absorption spectra, 1.53 μm band fluorescence spectra, Raman spectra and differential scanning calorimeter (DSC) curves. It is found that for Er3+-doped tellurite glass, besides improving its thermal stability, introducing SiO2 is helpful for the further improvement of the fluorescence full width at half maximum (FWHM) and bandwidth quality factor. The results indicate that the prepared Er3+-doped tellurite glass containing an appropriate amount of SiO2 has good prospect as a candidate of gain medium applied for 1.53 μm broadband amplifier.

Structure and spectroscopic properties of Er3+/Ce3+ co-doped TeO2-Bi2O3-TiO2 glasses modified with various WO3 contents for 1.53 μm emission

The Er3+/Ce3+ co-doped tellurite-based glasses (TeO2-Bi2O3-TiO2) modified with various WO3 contents are prepared using conventional melt-quenching technique. The X-ray diffraction (XRD) patterns and Raman spectra of glass samples are measured to investigate the structures. The absorption spectra, the up-conversion emission spectra, the 1.53 μm band fluorescence spectra and the lifetime of Er3+:4I13/2 level are measured, and the amplification quality factors of Er3+ are calculated to evaluate the effect of WO3 contents on the 1.53 μm band spectroscopic properties. With the introduction of WO3, it is found that the prepared tellurite-based glasses maintain the amorphous structure, while the 1.53 μm band fluorescence intensity of Er3+ is improved evidently, and the fluorescence full width at half maximum (FWHM) is broadened accordingly. In addition, the prepared tellurite-based glass samples have larger bandwidth quality factor than silicate and germanate glasses. The results indicate that the prepared Er3+/Ce3+ co-doped tellurite-based glass with a certain amount of WO3 is an excellent gain medium applied for the 1.53 μm band Er3+-doped fiber amplifier (EDFA).

Investigation of thermal stability and spectroscopic properties in Er 3+/Yb 3+ co-doped niobic tungsten tellurite glasses

A series of novel Er 3+/Yb 3+ co-doped 75TeO 2–(25 − x)Nb 2O 5– xWO 3 (TNW: x = 0, 3, 6, 9, 12, and 15 mol%) glasses have been prepared. Effect of WO 3 on the thermal stability and spectroscopic properties of Er 3+/Yb 3+ co-doped niobic tellurite glasses have been investigated. With WO 3 content increasing from 0 to 15 mol%, the fluorescence full width at half maximum (FWHM), the peak of stimulated emission cross-section ( σ e peak ), the measured lifetime ( τ m), and quantum efficiency ( η) change from 71 nm, 8.47 × 10 −21 cm 2, 2.86 ms, 84.1% to 76 nm, 7.22 × 10 −21 cm 2, 3.14 ms, 88.9%, respectively. The FWHM and σ e peak of Er 3+ ions in different glass hosts were compared; the obtained data reveals that this new TNW4 glass may be a potentially useful candidate material host for broadband amplifiers.

Investigation of thermal stability and spectroscopic properties in Er 3+ doped bismuth–boron–germanium glasses

A series of Er 3+-doped 50Bi 2O 3-(50- x)B 2O 3- xGeO 2+0.5 wt% Er 2O 3 ( x=0, 5, 10, 15, 20 mol%) glasses were prepared. The thermal stability, absorption spectra, emission spectra and lifetime of the 4I 13 / 2 level of Er 3+ ions were measured and studied. It is found that the absorption cross-section of Er 3+, emission intensity and lifetime of the 4I 13 / 2 level of Er 3+ increase with increasing GeO 2 content in the glass composition, while the fluorescence full-width at half-maximum (FWHM) at 1.5 μm of Er 3+ is about 79 nm in x=20 mol% glass sample under 970 nm pump. The obtained data suggest that this system glass can be used as a candidate host material for potential broadband optical amplifiers.

Investigation of spectral properties and thermal stability of Er3+/Yb3+ co-doped TeO2-B2O3-SiO2 glasses

A series of Er3+/Yb3+ co-doped (85-x) TeO2-15B2O3-xSiO2 (TBS x=0,5,10,15,20 mol%) glasses have been prepared. The thermal stability, absorption and emission spectra, lifetime of Er3+: 4I13/2 level and infrared transmit spectra were measured and discussed. The emission spectra of Er3+:4I13/2→4I15/2 transition was analyzed using a peak-fit routine, and an equivalent four-level system was proposed to estimate the Stark splitting for the 4I15/2 and 4I13/2 levels of Er3+ ions. It was found that the thermal stability of these glasses was improved by introducing SiO2. The difference between the glass transition temperature (Tg) and the crystallization onset temperature (Tx), ΔT=Tx-Tg, have came to 178℃ when SiO2 was 20 mol%, indicating that they were suitable for fiber drawing. The fluorescence full width at half maximum (FWHM) and peak of emission cross-section (σpeake) of Er3+ ions in different glass hosts have been compared. The results indicate that these new TBS glasses are promising host material for broadband amplifiers.TeO2-B2O3-SiO2, thermal stability, G

Effect of Ga 2O 3 on the spectroscopic properties of erbium-doped boro-bismuth glasses

The spectroscopic properties and thermal stability of Er 3+-doped Bi 2O 3–B 2O 3–Ga 2O 3 glasses are investigated experimentally. The effect of Ga 2O 3 content on absorption spectra, the Judd-Ofelt parameters Ω t ( t = 2, 4, 6), fluorescence spectra and the lifetimes of Er 3+: 4I 13/2 level are also investigated, and the stimulated emission cross-section is calculated from McCumber theory. With the increasing of Ga 2O 3 content in the glass composition, the Ω t ( t = 2, 4, 6) parameters, fluorescence full width at half maximum (FWHM) and the 4I 13/2 lifetimes of Er 3+ first increase, reach its maximum at Ga 2O 3 = 8 mol.%, and then decrease. The results show that Er 3+-doped 50Bi 2O 3–42B 2O 3–8Ga 2O 3 glass has the broadest FWHM (81 nm) and large stimulated emission cross-section (1.03 × 10 −20 cm 2) in these glass samples. Compared with other glass hosts, the gain bandwidth properties of Er 3+-doped Bi 2O 3–B 2O 3–Ga 2O 3 glass is better than tellurite, silicate, phosphate and germante glasses. In addition, the lifetime of 4I 13/2 level of Er 3+ in bismuth-based glass, compared with those in other glasses, is relative low due to the high-phonon energy of the B–O bond, the large refractive index of the host and the existence of OH − in the glass. At the same time, the glass thermal stability is improved in which the substitution of Ga 2O 3 for B 2O 3 strengthens the network structure. The suitability of bismuth-based glass as a host for a Er 3+-doped broadband amplifier and its advantages over other glass hosts are also discussed.

Effect of [formula omitted] content on the thermal stability and spectroscopic properties of [formula omitted] co-doped tellurite borate glasses

Er 3 + / Yb 3 + co-doped ( 85 - x ) TeO 2 – 15 B 2 O 3 – x SiO 2 (TBS x = 0 , 5, 10, 15, 20 mol%) glasses had been prepared. Effect of SiO 2 content on the thermal stability and spectroscopic properties of Er 3 + / Yb 3 + co-doped tellurite borate glasses have been investigated. With SiO 2 content increasing from 0 to 20 mol%, the T g and T x , the fluorescence full width at half maximum (FWHM), the peak of stimulated emission cross-section ( σ peak ), the measured lifetime ( τ m ) and quantum efficiency ( η ) change from 398 ∘ C , 530 ∘ C , 75 nm, 5.7 × 10 - 21 cm 2 , 1.84 ms, 56.4% to 419 ∘ C , 593 ∘ C , 71 nm, 7.5 × 10 - 21 cm 2 , 2.38 ms, 70.6%, respectively. The results indicate that for Er 3 + / Yb 3 + co-doped tellurite borate glasses, introducing a suitable amount of SiO 2 content is helpful for the improvement of thermal stability and the incremental of the lifetime of I 13 / 2 4 level and quantum efficiency of Er 3 + : I 13 / 2 4 → I 15 / 2 4 transition, while keeping the FWHM relatively large.

The spectroscopic properties of Er 3+-doped TeO 2–Nb 2O 5 glasses with high mechanical strength performance

(100 − x)TeO 2 − xNb 2O 5 ( x = 5–20) niobic tellurite glasses doped with 0.5 mol.% Er 2O 3 were synthesized, and their thermal, mechanical, and spectroscopic properties were measured and compared to the properties of the typical 75TeO 2–20ZnO–5Na 2O (TZN) tellurite glass. The refractive index ( n d), density ( ρ), and glass transition temperature ( T g) of bulk glasses increase with the Nb 2O 5 content. The Vickers microhardness ( H v) of bulk glass in niobic tellurite glasses also increases with the Nb 2O 5 content. The values (2.5–3.2 GPa) of H v in the niobic tellurite glasses are 47–88% larger than that (1.7 GPa) in TZN glass. The effect of Nb 2O 5 content on absorption spectra, the Judd–Ofelt parameters Ω t ( t = 2, 4, 6), fluorescence spectra and the lifetimes of Er 3+:I 13/2 level were also investigated, and the stimulated emission cross-section was calculated from McCumber theory. With increasing Nb 2O 5 content in the glass composition, the Ω t ( t = 2, 4, 6) parameters, fluorescence full width at half maximum (FWHM) of I 13/2 of Er 3+ increase, while the 4I 13/2 lifetimes of Er 3+ decreases. Compared with TZN glass, the gain bandwidth properties of Er 3+-doped TeO 2–Nb 2O 5 glass is much larger than in tellurite glass based TeO 2–ZnO–Na 2O system, bismush-based glass, germanate, and silicate glasses, which indicates that TeO 2–Nb 2O 5 glasses are better choice as a practical available host material for broadband Er 3+-doped amplifier.

Spectral properties and thermal stability of Er3+/Yb3+ codoped tungsten–tellurite glasses

The spectral properties of Er3+/Yb3+ codoped tungsten–tellurite glasses are investigated based on the Judd–Ofelt and McCumber theories. The compositional dependence of intensity parameter Ω2 is attributed to the covalency of Er–O bonds for TeO2–WO3–La2O3 and TeO2–WO3–Bi2O3 glasses while for TeO2–WO3–BaO glasses, Ω2 is mainly determined by the asymmetry in the local structures around Er3+ ions. The fluorescence full width at half maximum (FWHM) and the peak emission cross-section (σpeak) of the 4I13/2 → 4I15/2 transition of Er3+ ions in different glass hosts have been compared. The results indicate that the tungsten–tellurite glass is a promising host material for 1.55 μm broadband amplification.

Thermal stability, Judd–Ofelt theory analysis and spectroscopic properties of a new Er 3+/Yb 3+-codoped germano-tellurite glass

The Er 3+/Yb 3+-codoped 70TeO 2–5Li 2O–10B 2O 3–15GeO 2 glass was prepared. The thermal stability, absorption spectra, emission spectra and up-conversion spectra were measured and investigated. The Judd–Ofelt analysis based on absorption spectra was performed in order to determine the Judd–Ofelt intensity parameters Ω t ( t = 2, 4, 6), spontaneous emission probability, radiative lifetime and branching ratios of several Er 3+ transitions. It was found that this studied glass has good thermal stability, broad fluorescence full width at half maximum (FWHM), large stimulated emission cross-section and strong up-conversion emissions at about 532, 546 and 659 nm, corresponding to the 2H 11/2 → 4I 15/2, 4S 3/2 → 4I 15/2 and 4F 9/2 → 4I 15/2 transitions of Er 3+, respectively under the excitation at 970 nm. The results suggest that this Er 3+/Yb 3+-codoped germano-tellurite glass may be a potentially useful material for developing potential amplifiers and up-conversion optical devices.

Effect of Bi2O3 on spectroscopic properties of Er3+-doped lead oxyfluorosilicate glasses for broadband optical amplifiers

The spectroscopic properties of Er3+-doped lead oxyfluorosilicate glasses were analyzed with Judd–Ofelt and McCumber theories. The obtained data suggest that the fluorescence full width at half maximum (FWHM) is related to the Ω6 parameter, the larger the Ω6 parameter, and the broader the FWHM. The results showed that Er3+-doped 45SiO2–5Bi2O3–50PbF2 glass had the broadest FWHM (64nm) and large stimulated emission cross-section (0.73×10−20cm2) in these glass samples. Compared with other glass hosts, the gain bandwidth properties of Er3+-doped 45SiO2–5Bi2O3–50PbF2 glass is close to those of tellurite and bismuth glasses, and has advantage over those of silicate, phosphate and germante glasses. The results suggest that Er3+-doped 45SiO2–5Bi2O3–50PbF2 glass can be used as potential host material for developing broadband optical amplifiers in wavelength-division-multiplexing network system.

Study of luminescence properties of novel Er 3+ single-doped and Er 3+/Yb 3+ co-doped tellurite glasses

The novel Er 3+ single-doped and Er 3+/Yb 3+ co-doped tellurite glasses were prepared. The effect of Yb 2O 3 concentration on absorption spectra, emission spectra and upconversion spectra of glasses were measured and investigated. The emission intensity, fluorescence full width at half maximum (FWHM) and upconversion luminescence of Er 3+ go up with the increasing concentration of Yb 3+ ions. The maximum FWHM of 4I 13/2 → 4I 15/2 transition of Er 3+ is approximate 77 nm for 1.41 × 10 21 ions/cm 3 concentration of Yb 3+-doped glass. The visible upconversion emissions at about 532, 546 and 659 nm, corresponding to the 2H 11/2 → 4I 15/2, 4S 3/2 → 4I 15/2 and 4F 9/2 → 4I 15/2 transitions of Er 3+, respectively, were simultaneously observed under the excitation at 970 nm. Subsequently, the possible upconversion mechanisms and important role of Yb 3+ on the green and red emissions were discussed and compared. The results demonstrate that this kind of tellurite glass may be a potentially useful material for developing potential amplifiers and upconversion optical devices.

Thermal Stability and Spectroscopic Properties of NewEr3+/Yb3+-Codoped Tellurite Glasses

A series of new Er3+/Yb3+-codoped70 TeO2–5 Li2O–(25-x)B2O3–xGeO2 (TLBG,x = 0, 5, 10, 15, 20 mol%) glasses are prepared.The thermal stability and spectroscopic properties of TLBG glasses arestudied. It is found that these glasses have the better thermalstability ((Tx−Tg)>150 degrees C) comparedwith 75 TeO2–20 ZnO–5Na2O (TZN) glass. The fluorescencefull width at half maximum (FWHM) is about 77 nm, while the emissionintensity and the quantum efficiency of the 4I13/2level of Er3+ increase with the increasing GeO2 content.The maximum quantum efficiency and stimulated emission cross-section ofEr3+ calculated from the McCumber theory are 93.82% and9.0×10−21 cm2, respectively. The products of FWHMand σepeak of Er3+ in TLBG glasses are larger thanthose in other reported glasses. The obtained data indicate that thiskind of TLBG glasses is a promising candidate host material forEr3+-doped broadband amplifiers.

Spectral properties and thermal stability of Er 3+-doped oxyfluoride silicate glasses for broadband optical amplifier

Er 3+-doped 50SiO 2–(50− x)PbO– xPbF 2 glasses were prepared. The effect of PbF 2 content on refractive indices, densities, absorption spectra, the Judd–Ofelt parameters Ω t ( t=2,4,6), fluorescence spectra and the lifetimes of 4 I 13/2 level of Er 3+ in 50SiO 2–(50− x)PbO– xPbF 2 glasses were investigated, and the stimulated emission cross-section was calculated from McCumber theory. With increasing PbF 2 content in the glass composition, the Ω 6 parameter, fluorescence full width at half maximum (FWHM) and lifetimes of 4 I 13/2 level of Er 3+ increase, while refractive indices and densities decrease. Compared with other glass hosts, the gain bandwidth properties of Er 3+-doped 50SiO 2–50PbF 2 glass is close to those of tellurite and bismuth glasses, and has an advantage over those of silicate, phosphate and germante glasses. The broad and flat 4 I 13/2→ 4 I 15/2 emission of Er 3+ around 1.55 μm can be used as host material for potential broadband optical amplifier in the wavelength–division–multiplexing (WDM) network system.

Mixed Former Effect: A Kind of Composition Adjusting Method ofEr-Doped Glass for Broadband Amplification

A compositional adjusting method called the mixed former effect isproposed to improve effectively optical properties such as the emissioncross section, the fluorescence full width at half maximum (FWHM) and the lifetimeof the 4I13/2 level of Er-doped glass. A kind of Er-dopedbismuth-based glass illustrated high emission cross section(σep = 0.66-0.90 pm2), large fluorescenceFWHM (68-85 nm), and relatively long lifetime of the4I13/2 level (τm = 1.6-4.3 ms) using this method.A comparison of spectroscopic parameters shows that bismuth-based glass ismuch better for broadband amplifiers than other glass hosts.