McCumber Theory Research Articles

Comparative study of spectroscopic properties of Er3+-ion doped K2O/KF-Gd2O3-P2O5 glass systems

The two phosphate glasses with composition 17K2O−17Gd2O3−65P2O5−01Er2O3 and 17KF−17Gd2O3−65P2O5−01Er2O3 composition were synthesized by conventional-melt quenching techniques to study comparatively the spectroscopic, Judd–Ofelt (JO), radiative properties and NIR-luminescent properties. The Urbach energy of K2O−Er and KF-Er samples was 0.3547 and 0.4799 eV. The observed trend is Ω2>Ω4>Ω6 and Ω2>Ω6>Ω4 for JO-intensity-parameters for K2O−Er and KF-Er glasses. Moreover, K2O−Er has higher Ω4 and Ω6 values, thus having more rigidity and viscosity than KF-Er. The measured values of full-width-half-maximum (FWHM) for K2O−Er and KF-Er glasses 54.60 and 58.27, respectively. The measured values of FWHM for K2O−Er and KF-Er glasses were 54.60 and 58.27, respectively. The A R values are 417.61 and 3038 for K2O−Er and KF-Er glasses, respectively. The radiative lifetime (τ R ) for K2O−Er and KF-Er glasses is 2.39 ms and 3.18 ms, respectively. Utilizing McCumber theory the G(λ,β) is positive and population-inversion is more than 0.4 for both glasses. Both samples have flat gain-bandwidth in the range of 1505–1585 nm, which covers the S-, C-, and L-bands of the low-loss optical communication-window. It is evident from all these results that the prepared glass samples have the potential for a low-threshold and high gain NIR laser and optical-fiber amplifier.

Broadband near infrared emission of Er3+ ions doped fluorophosphate glasses for solid state laser applications

A series of glass compositions (P2O5 + Bi2O3 + Na2CO3 + SrF2 + xEr2O3) with different concentrations of erbium ions (Er3+) was synthesized using the melt quenching method and the samples were subjected to thorough characterization to explore their optical and structural properties. In order to ascertain the amorphous nature of the glass and acquire a deeper understanding of its chemical bonding, conventional methods of characterization, such as X-ray diffraction and Fourier transform infrared spectroscopy, were utilized. The Judd-Ofelt intensity parameters were computed using the absorption spectra of glasses doped with Er3+, providing vital information about the local environment and coordination of Er3+ ions in the glass matrix. Using the Judd-Ofelt intensity parameters and emission spectra to calculate the radiative parameters like total radiative transition probability (AT), radiative lifetime (τR) and radiative branching ratios for 4I13/2 → 4I15/2 transition. The McCumber theory is used to study absorption and emission cross-section for 4I13/2 → 4I15/2 transition. Prepared the PBNSEr05 glass sample suitable candidates for 1.53 μm solid state laser applications.

Laser cooling ytterbium doped silica by 67 K from ambient temperature.

Laser cooling of a 5 cm long, 1 mm diameter ytterbium doped (6.56×1025 ions/m3) silica rod by 67 K from room temperature was achieved. For the pump source, a 100 W level ytterbium fiber amplifier was constructed along with a 1032 nm fiber Bragg grating seed laser. Experiments were done in vacuum and monitored with the non-contact differential luminescence thermometry method. Direct measurements of the absorption spectrum as a function of temperature were made, to avoid any possible ambiguities from site-selectivity and deviations from McCumber theory at low temperature. This allowed direct computation of the cooling efficiency versus temperature at the pump wavelength, permitting an estimated heat lift of 1.42 W/m as the sample cooled from ambient temperature to an absolute temperature of 229 K.

A route for determining absorption and emission cross-sections of rare-earth luminescence centers based on McCumber theory and Einstein coefficients

McCumber theory describes the relationship between the absorption cross-section and the emission cross-section of ionic luminescence centers. This theory is frequently used for determining absorption and emission cross-sections.

Broadband 1.53 μm Emission and McCumber Analysis of Er3+ Doped Alkali Oxyfluorophosphate Glass for Fiber Optic Communication Material

Er3+ doped alkali oxyfluorophosphate glasses were prepared by the melted quenching method and characterized their optical and photoluminescence properties. Firstly, the chemical compositions of glasses were varied by changing alkali fluoride (LiF and NaF), whereas the concentration of Er3+ was fixed at 1.00 mol%. The optical absorption pattern and intensity were resemblance. Broadband 1.53 μm emission was one prominent peak of Er3+ in glass and the highest emission intensity was obtained for NaF glass under the stimulating at 521 nm. Secondly, the NaF glass was prepared by variation of Er3+ concentration (0.1, 0.5, 1.0, 2.0, and 4.0 mol%). The emission intensity of glasses increases with an increase in Er2O3 concentration up to 2.00 mol% and decreases for higher Er2O3 concentration, because of the concentration quenching effect. Broadband emission was observed that it covers three telecommunication windows: S, C, and L bands. The absorption and emission cross-section of 2.00 mol% of Er3+ doped alkali oxyfluorophosphate were found to be 1.3895 x 10−20 cm2 and 1.7248 x 1020 cm−2 , respectively by using the McCumber theory. Both values led to the estimate of the internal gain coefficient for 4I13/2→4I15/2 emission transition. The gain coefficient is positive when P is higher than 40%. All results point out that Er3+ doped alkali oxyfluorophosphate glass could be useful for fiber optic communication material.

Er3+: B2O3-TeO2-ZnO-PbF2−M2O/MF (M = Li, Na, and K) glasses: An inspection of structural, thermal, optical, chromatic, and near-infrared luminescence traits for displays and potential C-band amplification

Six 1.0 mol% Er2O3-doped lead fluoride zinc borotellurite glasses comprising different alkali metal oxides and fluorides (K2O, Na2O, Li2O, KF, NaF, and LiF) have been synthesized via melting and quick-quench approach and structural, thermal, optical, chromatic, upconversion, and NIR (near-infrared) emission features and fluorescence decay times were explored. Main structural units BO3 and BO4, as well as TeO4 and TeO3, are affirmed in all glasses networks by Fourier transform infrared and Raman spectroscopy. For transition 4I13/2 →4I15/2, σemi (emission cross-section) has been assessed by applying Füchtbauer–Ladenburg and McCumber's theories. For Li2O and NaF constituting glasses, acquired peak absorption cross-section (4I15/2→4I13/2) values are 0.999 × 10−20 cm2 and 1.093 × 10−20 cm2, while σemiM (4I13/2→4I15/2) values are 1.064 × 10−20 cm2 and 1.174 × 10−20 cm2 individually. At various P (population inversion) values, calculated gain spectra revealed the C- band amplification from P = 40%.

McCumber analysis of Er3+ doped Al-Ba-Li phosphate glasses for optical amplifier material

Er3+-doped Al-Ba-Li phosphate glasses were produced using a melt-quenching method. In the current study, the effect of doping Er3+ ion concentration for photoluminescence efficiency and developing compact optical amplifiers operating at 1.53 μm was investigated. The optical absorption study reveals that ten absorption peaks, showing highest intensity at 522 nm and 980 nm in UV-Vis and NIR regions, respectively. Mc-Cumber theory was used to conduct and analyse the optical absorption measurements obtained. The maximum intensity was observed at 4I13/2→4I15/2 transition in the wavelength range of 1400–1700 nm, which is monitored using 980 nm. The highest emission intensity was observed for 1.5 mol% of Er3+ ions doped glass in the NIR emission spectra. The McCumber theory was applied to evaluate the emission cross-sections; for 1.5 mol% of Er3+ ions, the emission cross-section and gain bandwidth value show 9.02 10−21 cm2 and 1.16 1025 cm3 respectively. When the concentration of Er3+ ions increased from 0.1, 0.5, 1.0, 1.5, and 2.0 mol%, respectively, the lifetime () of the 4I13/2 level reduced from 1.45, 1.19, 0.93, 0.72, and 0.63 ms. The population inversion values show larger than 0.4, suggesting their potential suitability in broadband amplifiers used in C-band communication for a typical population inversion of more than 40%. Phosphate glass doped with Er3+ ions at a concentration of 1.5 mol% doped glass being potential candidate for solid-state optical amplifying devices.

Up-conversion and near-infrared luminescence in Er3+ -doped La2O3-PbO-B2O3-TeO2 glasses for the generation of fibre amplifiers and green LED applications

In this work, we demonstrate the influence of Er3+ ions on the spectroscopic properties of 5La2O3-15PbO-(50-x)B2O3-xEr2O3-30TeO2 glasses doped with x = 0.1, 0.5, 1.0, 2.0 & 3.0 mol% of Er3+ were prepared with the melt-quenching method. The structural, fluorescence and decay time properties were examined, and the theoretical model, JO, Mc, and FL theory, was utilised to confirm the experimental findings. It is evident from XRD results that the glasses do not possess a well-defined crystalline structure. Instead, they exhibit a random arrangement of atoms and molecules, indicating an amorphous characteristic. JO analysis yields the stimulated-emission cross-section (2.12 ×10−20 for LPBTE1 glass, which is highest among other prepared glasses) & intensity parameters (Ω2,4,6) show Ω2 > Ω6 > Ω4 trend indicating the covalency nature. Predominant luminescence in the NIR region, emission peaked at 1537 nm was observed, which was ascribed to the 4I13/2⟶4I15/2 transition. The temporal decay rate decreased from 0.83 ms to 0.27 ms with an increase in the concentration of Er3+ from 0.1 to 3 mol%, which is due to the self-quenching action of the cross-relaxation channels. Furthermore, using Mc-Cumber's theory the peak values for the emission and absorption cross-sections are evaluated and found in good agreement with each other. The gain profile demonstrates more than 40% population inversion between 1530 and 1610 nm in the C +L band. In addition, the up-conversion of 4S3/2⟶4I15/2 transitions at 544 nm exhibits green emission shows two-photon absorptions. Overall, the investigated results demonstrate that the prepared Er3+ -doped La2O3-PbO-B2O3-TeO2 glasses are the best choice for optical fibre applications.

NIR emission and up-conversion spectral studies of Er/Yb co-doped B2O3-Bi2O3-NaF-BaF2 glasses for optical amplifiers and laser applications

Er-singly and Er/Yb-codoped oxyfluoride glasses were prepared by conventional melt-quenching technique. Structural, optical, steady-state and time-resolved spectroscopy studies were performed. The down-conversion (DC) and up-conversion (UC) mechanisms in the Er3+, Yb3+ (single) and Er3+/Yb3+ (co-doped) systems were investigated under 980 nm laser excitation and the energy transfers involved in the emissions of Er3+ and Yb3+ ions were discussed. Judd-Ofelt intensity and radiative factors such as absorption cross-section (σabs) and emission cross-sections (σemi) were evaluated and an enhanced σemi was observed for the co-doped (1 mol% Er/1 mol% Yb) glasses. Gain cross-section profiles were estimated based on σabs and σemi from McCumber theory for the 4I13/2 ↔ 4I15/2 transitions. At the same time, the studied glasses also exhibited intense UC transitions from the excited states of 2H11/2, 4S3/2, and 4F9/2 to the 4I15/2 ground state of Er3+ ions and covered the strong green and red spectral regions. Time-resolved spectroscopic measurements are extended for NIR and UC emission transitions were discussed in detail.

Effect of Erbium Oxide on Luminescence and Spectroscopy Properties of a Zinc Barium Boro‐Tellurite Glass System for Photonic Applications

This research investigates the luminescence and spectroscopy properties of boro‐tellurite glass doped with Er3+ ions. The series of glass is (30−x)TeO2–30B2O3–10ZnO–30BaO–xEr2O3 where x = 0.00, 0.05, 0.10, 0.50, 1.00, and 1.50 mol%. The glass is synthesized by melt‐quenching technique. The physical properties such as density and molar volume are evaluated. The concentration quenching effect is observed at 1.00 mol% of Er2O3 concentration. The molar volume and density of the present glasses show an opposite trend with increasing Er2O3 concentration suggesting more structural degradation due to non‐bridging oxygen. The strongest intensity of absorption spectra occurs at 525 nm. The emission spectra shows an emission peak at 1.54 μm of 4I13/2 → 4I15/2 transition when monitored at 525 nm. Judd–Ofelt (J–O) analysis is employed to calculate the oscillator strength, stimulated emission cross‐section, branching ratios, and a radiative lifetime of the prepared glass samples. McCumber theory is employed to understand the gain coefficients of the glasses. The data obtained reveal that these glasses doped Er3+ ion suits to be a potential candidate for C‐band optical communication devices.

Sensitization effect of Nd3+ ions on Yb3+/Nd3+ co-doped oxyfluoride glasses and study of their optical, fluorescence, and upconversion abilities for visible laser and NIR amplifier applications

The development of laser technology has created intense demand for optical confinement materials with high performance. Herein the authors have been investigated Yb 3+ -singly doped and Yb 3+ /Nd 3+ -codoped SiO 2 -based oxyfluoride glasses in terms of their optical absorption, and their near-infrared (NIR) and up-conversion (UC) emissions including emission decay profiles. Under 808 nm laser diode (LD) excitation, four NIR emission bands were observed i.e., (Nd 3+ : 4 F 3/2 → 4 I 9/2 , Yb 3+ : 2 F 5/2 → 2 F 7/2 , Nd 3+ : 4 F 3/2 → 4 I 11/2 , and Nd 3+ : 4 F 3/2 → 4 I 13/2 ) in co-doped glasses. NIR emission cross-sections [ (σ emi ) stimulated, (σ M emi ) from Mc-cumber theory] were calculated for 2 F 5/2 → 2 F 7/2 (∼1030 nm) transition of Yb 3+ ion. σ emi was found to be highest (26.27 × 10 −21 cm 2 ) for the Yb 3+ : 2 F 5/2 → 2 F 7/2 transition in N2 glass. UC emission spectra recorded at 980 nm LD show bands centered at 500, 536, 595 & 610, and 664 nm, attributed to 4 G 9/2 → 4 I 9/2 , 4 G 7/2 → 4 I 9/2 & 4 G 7/2 → 4 I 11/2, 4 G 5/2 → 4 I 9/2 , and 4 G 9/2 → 4 I 13/2 transitions, respectively. Decay profiles were analyzed for Yb 3+ : 2 F 5/2 → 2 F 7/2 (∼1030 nm) and Nd 3+ : 4 F 3/2 → 4 I 11/2 (∼1057 nm) transitions at 808 nm LD. Energy transfer (ET) process from Nd 3+ to Yb 3+ in present glasses were detailed.

Er3+-doped barium sodium borate glasses development for 1.54 µm broadband amplifier and optical laser

Er3+-doped BaNaB glasses with 0.5, 1.0, 2.0, 3.0 and 4.0 mol% of Er3+ were prepared by melt-quenching technique for study their luminescence properties in NIR and visible regions. The absorption spectra showed the absorption bands at 381, 406, 451, 488, 522, 545, 653, 804, 977 and 1532 nm in UV-Vis-NIR region. The NIR emission spectra, excited with 977 nm, show the broad band centered at 1540 nm in the range of 1460–1625 nm covers the S, C and L bands that have low transmission loss region in fiber-optic communication. The glass sample with 3.0 mol% of Er3+ provides the highest intensity of NIR emission. From the Judd-Ofelt analysis and McCumber theory, the glass sample with 4.0 mol% of Er3+ show the best performance for use as a broadband amplifier with the high gain bandwidth at 633.64 × 10−28 cm3 and the high emission cross section at 7.51 × 10−21 cm2. For the emission in visible region, when excited with 349 nm, the glass sample with 3.0 mol% of Er3+ provides the most intense emission in yellow-green region, when excited with 402 nm, the glass sample with 4.0 mol% of Er3+ provides the most intense emission in green region. The results from the McCumber theory and gain efficiency show good agreement of the glass sample with 4.0 mol% of Er3+ for use as broadband amplifier in C and L communication windows when the population inversion is more than 50%.

Analysis of Optical and Near-Infrared Luminescence of Er3+ and Er3+/Yb3+ Co-Doped Heavy Metal Borate Glasses for Optical Amplifier Applications

For the near-infrared emission, Er3+ and Er3+/Yb3+ co-activated borate based glass hosts were synthesized by the method of melting andquenching. The emission intensity was maximum for 0.5 mol% Er3+ singly activated glass in the near-infrared (NIR) region covering the telecommunication window. The 2 mol% of Yb3+ co-doping enhanced the emission gain cross-section of the glass by two times contrast to 0.5 mol% Er3+ loaded glass. This enhancement shifted to lower spectral regions when P increased from 0 to 1. The effect of Yb3+ loading on the gain cross-section of the Er3+ co-activated glasses was analyzed using the McCumber theory. The results showed that the 0.5Er2Yb glass has a flat gain in the range of 1460–1640 nm, this suggest a lower pump threshold is enough to perform the laser functioning of a 1530 nm band and optical window of telecommunication applications.

Assessment of optical and fluorescence aspects of Er3+-doped multicomponent B2O3 glasses as active media for 1.532 μm near-infrared optical amplifiers

Current work principally provides an idea on controlling the Er3+: NIR (near-infrared) emission characteristics by changing a glass constituent and finding a suitable glass host favorable to design a novel C-optical band (1.53–1.565 μm) amplifier. By melting and rapid quench route, six transparent Er3+ (1 mol%)-doped B2O3-rich glasses having different single and mixed alkali ions were fabricated, and optical and fluorescence (visible and NIR) traits including Er3+ ion upper-levels 4S3/2 and 4I13/2 decay dynamics were inspected for such samples. At 1.4–1.65 μm wavelength range, an intense and wide NIR luminescence band centered at 1.532 μm (Er3+: 4I13/2 → 4I15/2 transition) has been obtained by a 980 nm laser diode pumping (4I15/2 → 4I11/2). NIR fluorescence Δλeff (effective bandwidth) varied depending on added single or mixed alkali ions, and a maximum Δλeff ∼74.66 nm was acquired for Er3+: Li ions constituting glass. For the 4I13/2 → 4I15/2 transition, σemi (stimulated emission cross-section) was evaluated using both Füchtbauer–Ladenburg and McCumber's theories. In all glasses, comparably, higher gain bandwidth (= 5.384 × 10−26 cm3) and peak σemiM (= 1.692 × 10−20 cm2) values have been attained for 4I13/2 → 4I15/2 transition in Li ions containing sample, and also this glass possesses the largest σabs (absorption cross-section) (= 1.459 × 10−20 cm2) for 4I15/2 → 4I13/2 transition. Further, at distinctive P (population inversion) values, gain spectra were computed, and all samples show C-optical band amplification beginning from P = 50%. All analyzed NIR fluorescence results indicate that Li ions having glass could be a potential gain medium for fiber amplifiers.

Erbium(III) ion-doped borate-based glasses for 1.53 μm broad band applications.

Novel erbium(III) ion-doped borate-based glasses (Er3+ :BCNF) by conventional melt-quenching technique were designed and synthesized. The glasses were characterized for their structural, vibrational and spectroscopic properties. The nephelauxetic ratio, bonding parameters, and Judd-Ofelt (JO) intensity parameters (Ωλ λ = 2, 4 and 6) were determined by using absorption spectrum of 1mol% Er2 O3 doped glass. These JO parameters were utilized to derive radiative properties for various excited states of erbium(III) ions. Emission cross-section for 4 I13/2 → 4 I15/2 transition of erbium(III) ions was computed through McCumber theory. The decay curves for (2 H11/2 , 4 S3/2 ) and 4 I13/2 levels were recorded and analysed. All the results of Er3+ :BCNF glasses revealed that the studied glasses are efficient and thermally stable and could be suitable for display devices, optical amplification and green laser applications.

Efficient UV-visible emission enabled by 532 nm CW excitation in an Ho3+-doped ZBLAN fiber.

Rare-earth-doped ZBLAN (ZrF4-BaF2-LaF3-AlF3-NaF) fibers have evolved to become promising candidates for efficient UV-visible emission because of their low phonon energy and low optical losses, as well as their well-defined absorption bands. We investigate the efficient emission of UV-visible light in a low-concentration (0.1 mol%) Ho3+-doped ZBLAN fiber excited by a 532 nm CW laser. In addition to the direct populating of the thermalized 5F4+5S2 levels by ground-state absorption, the upconversion processes responsible for UV-visible emission from the higher emitting levels, 3P1+3D3, 3K7+5G4, 5G5, and 5F3, of the Ho3+ ions are examined using excited-state absorption. The dependence of UV-visible fluorescence intensity on launched green pump power is experimentally determined, confirming the one-photon and two-photon characters of the observed processes. We theoretically investigate the excitation power dependence of the population density for nine Ho3+ levels based on a rate equation model. This qualitative model has shown a good agreement with the measured power dependence of UV-visible emission. Moreover, the emission cross-sections for blue, green, red, and deep-red light in the visible region are measured using the Füchtbauer-Ladenburg method and corroborated by McCumber theory, and the corresponding gain coefficients are derived. We propose an alternative approach to achieve efficient UV-visible emission in an Ho3+-doped ZBLAN fiber using a cost-effective, high-brightness 532 nm laser.

Optical and visible and near-infrared fluorescence aspects of Er3+, Tm3+, and Nd3+-doped B2O3-rich glasses for fiber amplifiers and NIR lasers

For synthesized each 1 mol% Er3+, Tm3+, and Nd3+-doped borate-rich glasses, optical and luminescence traits including fluorescence decay dynamics were explored. For Er3+: glass, at 1.4–1.65 μm range a wide NIR (near-infrared) luminescence band centered at 1.531 μm (4I13/2 → 4I15/2) and in Tm3+: glass, at 1.35–1.6 μm span a broad NIR fluorescence band centered at 1.458 μm (3H4→3F4) are obtained by 980 nm LD (laser diode) pumping (4I15/2 → 4I11/2) and 808 nm LD excitation (3H6→3H4) separately. Under 808 nm LD pumping (4I9/2 → 4F5/2+2H9/2), in Nd3+: glass, three emission bands peaked at 0.901 μm (4F3/2 → 4I9/2), 1.057 μm (4F3/2 → 4I11/2), and 1.329 μm (4F3/2 → 4I13/2) respectively are observed and in all such emissions, comparably the one obtained from transition 4F3/2 → 4I11/2 is highly intense. For acquired main visible and NIR emissions, Δλeff (effective bandwidth), by Füchtbauer–Ladenburg approach σemi (stimulated emission cross-section), gain bandwidth, and optical gain are evaluated. 75.73 nm, 113.67 nm, and 57.37 nm are the Δλeff values for Er3+: 4I13/2 → 4I15/2, Tm3+: 3H4→3F4, and Nd3+: 4F3/2 → 4I13/2 transitions accordingly. Using McCumber's theory, the calculated peak σemi for Er3+: 4I13/2 → 4I15/2 and Nd3+: 4F3/2 → 4I9/2 transitions are 1.495 × 10–20 cm2 and 0.5556 × 10–20 cm2, respectively. 4I13/2 → 4I15/2 transition gain cross-section spectra reveals C-band amplification at P (population inversion) = 50% in Er3+: glass, whereas at P = 30% for 4F3/2 → 4I9/2 transition gain cross-section is positive for lasing action at ∼0.9 μm in Nd3+: glass. All analyzed NIR luminescence outcomes reveal that studied glasses could be potential gain media for C-, S-, and O-bands fiber amplifiers and solid-state lasers.

Energy transfer and broad-band luminescence of Nd3+-Er3+ co-doped Lithium Fluorophosphate (LFP) glasses

Nd3+-Er3+co-doped lithium fluorophosphate (NdEr) glasses with broad-band emission were made by the traditional melt quenching technique. These glasses were characterized through physical, absorption spectra, NIR luminescence properties and structural studies using XANES. The absorption spectra of this work showed an increase with the increasing concentration of Er2O3 in the glass. The Near-Infrared (NIR) luminescence spectra were obtained from several excitation sources. The energy level diagram studied the interraction process and energy transfer mechanism. The emission intensity of Er2O3 increases up to 1.5 mol%, the concentration quenching effect makes the emission 4F3/2 → 4I9/2, 4I11/2 and 4I13/2 Nd3+ intensity weaken, which means Nd3+→Er3+ energy transfer enhanced. The Judd-Ofelt (JO) theory investigations have been applied for Nd3+ ions and found that the trend follows Ω6>Ω4>Ω2. The stimulated emission cross-section is calculated in two ways: F u¨ chtbaueer Ladenburg (FL) method and Mc-Cumber theory. The decay time is found to be bi-exponential when monitored at λex = 581 nm and λem = 1061 nm. The XANES spectra of Nd LIII-edge were investigated and the absorption band showed at ∼6209.8 eV, confirming the presence of Nd3+. The XANES spectra of Er LIII-edge were investigated and the absorption band showed at ∼8362.5 eV, confirming the presence of Er3+.

Photoluminescence analysis of Er3+-ions Doped P2O5-Gd2O3/GdF3-BaO-ZnO glass systems

We develop two Er3+-ions-doped Phosphate glass systems, 69 P2O5-10Gd2O3-10BaO-10ZnO-1Er2O3 and 69 P2O5-10GdF3-10BaO-10ZnO-1Er2O3, labeled as ZBaFEr and ZBaOEr, respectively, by the melt-quenching technique and study systematically their physical, optical, and luminescence properties such as densities, refractive indexes, ultraviolet-visible near-infrared (UV-Vis-NIR) absorption, photoluminescence spectra in Vis-NIR region, CIE coordinates and lifetime. The absorption spectra revealed the Er3+ peaks at 378, 405, 451, 489, 522, 652, 803, 978, and 1537 nm, attributed to the transition from 4I15/2 level to 4G11/2, 2G9/2, 4F5/2, 4F7/2, 2H11/2, 4F9/2, 4I9/2, 4I11/2 and 4I13/2 levels, respectively. We find that at 380-nm excitation, the emission peak at 1543 nm in the near-infra-red (NIR) region has a higher intensity for ZBaFEr than for the ZBaOEr. Furthermore, we employ the Judd-Ofelt (JO) and McCumber theory to study the stimulated emission cross-section for 4I13/2→4 I15/2 transitions of Er3+ ion. We find the bandwidth-quality [FWHM x σemi(λ)] to be 249 and 274 for ZBaOEr and ZBaFEr, respectively. The NIR-emission for both glasses covers the S-, C- and L-band of low-less-communication-window. The present results suggest that these glasses can be potentially used in optical amplifiers and tunable lasers.

Spectroscopic Properties of Er3+ Doped Li2O-Al2O3-BaO-P2O5 and Na2O-Al2O3-BaO-P2O5 Glasses for Fiber Optic Communication Material

Erbium doped phosphate glasses with Li2O-Al2O3-BaO-P2O5-Er2O3 (Li glass) and Na2O-Al2O3-BaO-P2O5-Er2O3 (Na glass) composition were produced using the melt-quench method to determine their spectroscopic properties. The optical absorption and fluorescence spectra were used to analyze the spectroscopic properties. The Judd-Ofelt intensity parameters were determined from the absorption band intensities. The Ω2 parameter of a LABPEr glass is 1.50 × 10−20 cm2 that of a glass of s NABPEr glass is 0.41 × 10−20 cm2, which of the LABPEr glass is higher than the NABPEr glass. The radiative transition probability (AR) of LABPEr and NABPEr are 133.03 and 80.38 s −1, respectively. In predicting the emission cross-section of 4I13/2→4I15/2 transition from the absorption cross-section of 4I15/2→4I13/2 transition for Er3+ ions, the McCumber theory has been adopted. At 1.54 nm, intense broad infrared fluorescence was detected under 980 nm excitation. The optical gain G(λ) properties can be derived from the σa and σe values that the gain is positive for 50% population inversion in the 1536–1640 nm wavelength range.