scholarly journals Luminescence Properties and Judd–Ofelt Analysis of Various ErF3 Concentration-Doped BaF2 Crystals

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4221
Author(s):  
Andrei Racu ◽  
Marius Stef ◽  
Gabriel Buse ◽  
Irina Nicoara ◽  
Daniel Vizman

The influence of erbium ion concentration on the optical properties of BaF2:ErF3 crystals was investigated. Four ErF3 concentration (0.05, 0.08, 0.15 and 0.5 mol% ErF3)-doped BaF2 crystals were obtained using the Bridgman technique. Room temperature optical absorption in the 250–850 nm spectral range was measured, and the photoluminescence (PL) and decay times were also investigated. The Judd–Ofelt (JO) approximation was used, taking into account four absorption peaks (at 377, 519, 653 and 802 nm). The JO intensity parameters, Ωt (t = 2, 4, 6), were calculated. The influence of the ErF3 concentration on the JO parameters, branching ratio, radiative transition probability and radiative lifetime were studied. The obtained results were compared with measured values and with those reported in the literature. Under excitation at 380 nm, the well-known green (539 nm) and red (668 nm) emissions were obtained. The calculated and experimental radiative lifetimes were in millisecond range for green and red emissions. The intensity of the PL spectra varied with the Er3+ ion concentration. The emission intensity increased linearly or exponentially, depending on the ErF3 concentration. Under excitation at 290 nm, separate to the green and red emissions, a new UV emission band (at 321 nm) was obtained. Other research has not reported the UV emission or the influence of ErF3 concentration on emission behavior.

2013 ◽  
Vol 22 ◽  
pp. 298-304
Author(s):  
BEENA BHATIA ◽  
VISHAL PARIHAR

Glasses of the system: xB2O3-10Bi2O3-30Li2O-xPr6O11 where x =1, 1.5 and 2 were prepared by melt quenching technique. Optical absorption and emission spectra have been recorded. The intensities of f-f transition are calculated in term of Judd-Ofelt (JO) intensity parameters Ωλ (λ = 2, 4 and 6). Using the fluorescence data and these Ωλ parameters, various radiative properties like transition probability (Arad), branching ratio (βR), radiative lifetime (τR), and stimulated emission cross section (σp), of various emission lines have been evaluated. The branching ratio for 3P0→3H4 transition is 56% and the predicted spontaneous radiative transition probability rates are fairly high 16411 s−1. This is beneficial for lasing emission.


2012 ◽  
Vol 585 ◽  
pp. 279-283 ◽  
Author(s):  
Sunil Bhardwaj ◽  
Rajni Shukla ◽  
Sujata Sanghi ◽  
Ashish Agarwal ◽  
Inder Pal

Glasses having compositions 20B2O3.(79.5-x)Bi2O3.xSiO2(10 ≤ x ≤ 40) doped with 0.5 mol% of Sm3+ions were prepared by melt quench technique. The amorphous nature of the glasses was confirmed by X-ray diffraction studies. The spectroscopic properties of Sm3+ions in bismuth borosilicate glasses as a function of bismuth oxide were investigated using optical absorption and fluorescence spectra. The Judd-Ofelt theory has been employed to calculate transitions probability from the data of absorption cross-section of several f-f transitions. The intensity parameters Ω2is related to the symmetry of glass hosts, where as the parameter Ω6is inversely proportional to the rare earth oxygen (RE-O) covalency. The variation of Ω4with Bi2O3content has been attributed to rigidity of the samples. Using the Judd Ofelt intensity parameters the other radiative properties like radiative transition probability, radiative life time, branching ratio and the stimulated emission cross-sections of prepared BBSS glasses have been calculated. A bright fluorescent orange emission at 600 nm (4G5/2→6H7/2) of Sm3+ion has been investigated as a function of Bi2O3in host glass. The radiative transition probabilities of Sm3+ions are large in bismuth borosilicate glasses, suggesting the suitability of these glasses as potential candidate for laser application.


2013 ◽  
Vol 22 ◽  
pp. 408-415
Author(s):  
INDER PAL ◽  
ASHISH AGARWAL ◽  
SUJATA SANGHI ◽  
SANJAY ◽  
SUNIL BHARDWAJ

Glasses having composition 20CdOxBi2O3(79.5-x)B2O30.5Pr6O11 with x varying from 15 to 35 mol% have been synthesized. Optical absorption and fluorescence spectra were measured at ambient temperature. A close correlation is observed between the Bi2O3 content and the spectroscopic properties such as Judd-Ofelt intensity parameters Ωλ = (λ = 2, 4, 6) , radiative and structural properties of prepared glasses doped with Pr3+ ion. The variation of Ω2 with Bi2O3 content has been attributed to changes in the asymmetry of the ligand field at the rare earth (RE) ion site (due to structural change) and to changes in RE-O covalency, whereas the variation of Ω6 has been related to the variation in RE-O covalency. Following the luminescence spectra, various radiative properties like transition probability (Arad), radiative lifetime (τr), branching ratio (βr) and stimulated emission cross section (σ) have been calculated. The branching ratio for 3P0 → 3F2 transition of Pr3+ glass system arrive at 41 to 40%, respectively, and the predicted spontaneous radiative transition probability rates are high and varies from 14032 to 14864 s−1. In addition, the glass stability is improved in which the substitution of B2O3 for Bi2O3 strengthens the glass network structure. The bismuth based glass as a host for Pr3+ ion doped suggesting their suitability for laser applications.


Crystals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1155
Author(s):  
Jin Zhang ◽  
Zengzhe Xi ◽  
Xinzhe Wang ◽  
Hao Feng ◽  
Wei Long ◽  
...  

An Er3+/Sc3+ co-doped 0.68Pb(Mg1/3Nb2/3)O3-0.32PbTiO3 ferroelectric single crystal was grown by high-temperature flux method. The remnant polarization Pr is 27.97 µC/cm2 and the coercive field Ec is 8.26 kV/cm for [100] oriented crystal. Green (524 and 551 nm) and red (654 nm) emission bands are generated at the 980 nm excitation, which corresponds to the 2H11/2→ 4I15/2, 4S3/2→ 4I15/2 and 4F9/2→ 4I15/2 transitions of Er3+, respectively. Judd–Ofelt theory has been applied to predict the spectroscopic characteristics of the as-grown crystals. The obtained J–O intensity parameters Ωt (t = 2, 4 and 6) are Ω2 = 0.76 × 10−20 cm2, Ω4 = 1.0 × 10−20 cm2, Ω6 = 0.55 × 10−20 cm2. Spectroscopic characteristics, including optical transition probabilities, branching ratio, and radiative lifetime of Er3+ in the crystal, are determined. The calculated radiative lifetimes of 4I13/2 and 4I11/2 energy levels are 2.82 ms and 2.61 ms, respectively. These investigations provide possibilities for the crystal Pb(Mg1/3Nb2/3)O3-0.32PbTiO3:Er3+/Sc3+ to be a new type of multifunctional crystal integrating electricity-luminescence.


2009 ◽  
Vol 23 (27) ◽  
pp. 3235-3242
Author(s):  
LI DAI ◽  
YAN-QING SU ◽  
SHI-PING WU ◽  
CHAO XU ◽  
JING-JIE GUO ◽  
...  

A series of Ho : LiNbO 3 crystals with various concentration of Ho 2 O 3 were grown by Czochralski technique. Transmittance spectrum, absorption spectrum and modified Judd–Ofelt approach have been used to investigate its spectroscopic properties. Ho concentrations in crystals were analyzed by an inductively-coupled plasma optical emission spectrometry (ICP-OE/MS). The results of the spectroscopic analysis of transition strengths for Ho ion in a series of Ho : LiNbO 3 crystals with various Ho content are reported. It is concluded that all the Ωλ values of the Ho ion decrease with increasing Ho content. For Ho (4 mol%): LiNbO 3, the obtained intensity parameters and radiative lifetime of the 5 I 5 level are: Ω2=5.75×10-20 cm2, Ω4=22.69×10-20 cm2, Ω6=14.10×10-20 cm2, and τ=4.08 ms respectively. The results showed that the Ho 2 O 3-codoped LiNbO 3 crystal increases the Ho ion radiative lifetimes, but has less influence on the fluorescence branching ratio.


2018 ◽  
Vol 63 (7) ◽  
pp. 608
Author(s):  
Y. Yamsuk ◽  
P. Yasaka ◽  
N. Sangwaranatee ◽  
J. Keawkao

Zinc-barium-borate glasses with the composition (60 − x)B2O3–10ZnO–30BaO–xSm2O3 (where x = 0.5, 1.0, 1.5, 2.0 and 2.5 mol %) doped with Sm3+ ions have been prepared, and their physical and optical properties are investigated. The photoluminescence spectra recorded under the 403-nm excitation exhibited the emission bands at 564, 600, 647, and 710 nm corresponding to the transition 4 G5/2 →6 Hj (j = 5/2, 7/2, 9/2, 11/2), respectively. Judd–Ofelt intensity parameters (Ωl, l = 2, 4 and 6) have been evaluated, and the radiative transition probabilities, emission cross-section, and branching ratios for the excited levels of Sm3+ ionsare predicted. The lifetime of the 4 G5/2 level is found to decrease with an increase in the Sm3+ ion concentration.


2011 ◽  
Vol 233-235 ◽  
pp. 1227-1230 ◽  
Author(s):  
Hao Liang ◽  
Fang Xie

A dendritic type europium complex/silicone rubber has been prepared. According to the luminescence spectrum, the Judd-Ofelt theory was adopted to calculate the intensity parameters Ω2and Ω4. The total radiative transition rate (640.1 s-1), radiative lifetime (1.562 ms) and the stimulated emission cross-sections (46.19×10-22cm2) of the5D0exciting state have been evaluated. Analysis reveals that the europium (III) chelating polymer is promising for use in optical devices.


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