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1.
This paper reports the luminescence potential of the dysprosium ion (Dy3+)-doped (varying contents from 0.1 to 1.0 mol%) magnesium borate glasses prepared by the melt-quenching method. As-quenched samples were characterized systematically to determine the effects of various Dy3+ contents on their structure, physical and optical traits. The Judd−Ofelt (J−O) intensity parameters (Ω2, Ω4, Ω6) and radiative properties of the best sample (with 0.7 mol% of Dy3+ doping) was evaluated to complement the experimental optical data. The studied glasses revealed three luminescence emission peaks at 382 nm (4F9/2→6H15/2, intense Blue), 572 nm (4F9/2→6H15/2, intense Yellow) and 661 nm (4F9/2→6H11/2, weak Red) under the excitation wavelength of 347 nm. The emission intensity was first increased up to the Dy3+ content of 0.7 mol% and then quenched. The observed luminescence intensity quenching was due to the resonant energy transfer from the excited state to the neighbouring ground state of Dy3+. The obtained high value of Ω2 signified the strong degree of covalency between the Dy3+ and ligand environment. The optimum glass sample (with 0.7 mol% of Dy3+) showed higher values of the branching ratio and stimulated emission cross-cross section for the 4F9/2→6H15/2 (yellow) emission transition, indicating its potential as bright yellow luminescent material and high gain visible laser applications. 相似文献
2.
S. B. Fu B. J. Chen J. S. Zhang X. P. Li H. Zhong B. N. Tian Y. Z. Wang M. Sun X. Q. Zhang L. H. Cheng H. Y. Zhong H. P. Xia 《Applied Physics A: Materials Science & Processing》2014,115(4):1329-1333
The upconversion technique of rare-earth-doped glasses or crystals is a potential route for achieving short-wavelength lasers (SWLs). The optical gain is an important parameter for evaluating lasing medium performance. Therefore, upconversion luminescence in glass with composition of 70TeO2–9PbF2–10AlF3–10BaF2–1Er2O3 was demonstrated, and the small-signal optical gain was measured via an amplified spontaneous emission technique when the sample was excited with a 980 nm laser. It was found that the optical gain was as large as 4.0 dB/cm, thus indicating that this glass may be a good medium for SWLs. 相似文献
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We have observed grating-based morphological hole burning in Sm2+-doped glass powders at room temperature. When photobleaching on the 4f(6)-4f(5)5d transition of Sm2+ is combined with multiple light scattering, holes are produced in frequency and wave-vector domains. The hole profile depends on the amount of light absorption of Sm2+; it sharpens as the absorption decreases. The variation of the hole shape is explained theoretically based on a diffusion approximation. 相似文献
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ErS+-doped phosphor-tellurite glass for broadband short-length Er3+-doped fiber amplifier (EDFA) is fabricated and characterized. The differential value (△T) of onset crystalline temperature (Tx) and glass transition temperature (Ts) is 206°C. 相似文献
6.
J.J. Romero J. Johannsen M. Mond K. Petermann G. Huber E. Heumann 《Applied physics. B, Lasers and optics》2005,80(2):159-163
Lanthanum scandium borate (LSB) has been proved to be an interesting laser matrix when doped with Nd3+ and Er3+ ions. In this paper, we demonstrate that it is also a very efficient laser material when doped with Yb3+ ions. The main spectroscopic characteristics of the system are presented, showing very broad absorption and emission bands, comparable to those found in Yb-doped GdCOB and YCOB crystals. From spectroscopic measurements the relevant laser parameters have been obtained, and a tunability of about 50 nm could be deduced. Room-temperature, continuous-wave laser action of Yb-doped LSB is demonstrated at a wavelength of 1045 nm with a slope efficiency as high as 64%. PACS 42.55.Rz; 42.70.Hj; 78.55.-m 相似文献
7.
A third-order optical nonlinear effect in a spherical glass resonator doped with Sm(3+) ions has been observed on stimulated emission lines of the (4)G(5/2)-(6)H(7/2) transition, in which the excitation beam of an Ar(+) laser in a 488-nm single line is coupled with the glass resonator through a prism. A spherical form is produced during a free fall of fractional glasses in a longitudinal electric furnace configured vertically. The prism-coupled glass microsphere exhibits sufficient performance to confine photon energy as a resonance of light inside the sphere and offers the prospect of new applications to functional photonic circuits. 相似文献
8.
采用柠檬酸作燃烧剂,在柠檬酸-硝酸盐体系下制备了Gd2O3:Sm3+和Gd2O3:Sm3+,Na+纳米晶.用X射线衍射仪、透射电子显微镜、荧光光谱仪等对样品的结构、形貌和光致发光性能进行了分析.结果表明:所得纳米样品为纯立方相,晶粒尺寸约为30 nm.在室温下,用275 nm激发光激发各样品时,可观测到Sm3+离子的较强发光,其主发射峰位分别位于561.5,603.5,651.5 nm,分别对应着Sm3+离子的4G5/2→6H5/2,4G5/2→6H7/2和7G5/2→6H9/2的电子跃迁,其中以4G5/2→6H7/2跃迁的光谱强度最强.实验表明:Na+离子的掺入使得Sm3+离子的光发射强度显著增强.对引起样品荧光强度变化的原因进行了分析. 相似文献
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C. C. Santos I. Guedes J. P. Siqueira L. Misoguti S. C. Zilio L. A. Boatner 《Applied physics. B, Lasers and optics》2010,99(3):559-563
In a laser coherent combination, the phase detection and control is the most critical. Using the beat frequency method, consistence
of the phase in output beams can be ensured through real-time detection and correction for the phase change. Phase noises
are controlled by a liquid crystal phase modulator. At the same time, the liquid crystal polarization controller is used to
make the polarization state stable, which is good for the improvement of the combining efficiency. The wave length of the
main oscillation laser is 532 nm. The output power of laser can be adjusted continuously from 0 to 6 W. The shifted frequency
of the system is 40 MHz. The accuracy for phase control is superior to λ/70 RMS. In the process of closed-loop control, using the liquid crystal phase and polarization controller, a better signal
phase correction of optical path has been achieved for the coherent combination of high power laser arrays. 相似文献
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《Solid State Communications》1986,58(3):181-184
The system of Tm3+ and Pr3+ in barium borate glass is investigated for finding out the mechanism of nonradiative energy transfer at room temperature. The various constants for this system relevant to the energy transfer are also calculated. 相似文献
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Upconversion fluorescence spectroscopy of Er~(3+)-doped lead oxyfluorosilicate glass 总被引:6,自引:0,他引:6
Upconversion fluorescence emission of Er3+-doped oxyfluorosilicate glass excited at 975 nm is experimentally investigated. The results reveal that the intense green and red emission, and weak blue emission centered at 525, 543, 655, and 410 nm, respectively. A two-photon upconversion process is assigned to the green and red emission while a three-photon process is responsible for blue upconversion. The possible upconversion mechanisms are discussed based on excited state absorption and energy transfer between excited Er3+ ions. The intense upconversion fluorescence of Er3+-doped lead oxyfluorosilicate glass may be a potentially useful material for developing upconversion optical devices. 相似文献
15.
Calibo glasses of Sm3+ with and without BaO have been synthesized and the optical properties (like absorption and photoluminescence) analyzed in terms of Judd–Ofelt theory. The fluorescence yield of Sm3+ enhances with BaO, and is optimum at 10% BaO. The effect of temperature on the energy transfer probability in (Sm3+:Eu3+) codoped glass has been reported and it can be inferred that the combination may serve as a temperature sensor. PACS 42.70.Ce 相似文献
16.
Series of ternary glass systems namely, Na2O, B2O3, and RO (R=Ba or Mg) doped with TiO2 are synthesized. The present glasses are dictated by requirement for a small refractive index and a small nonlinear coefficient needed for waveguide and laser fabrication requirements. The effect of MgO and BaO as alkaline earth metals on the optical properties of the glass systems is investigated. The dependence of the refractive index and extinction coefficient dispersion curves on composition is carried out over a wavelength range of 0.3-. Applying a genetic algorithm technique, the parameters of Sellmeier dispersion formula that fit index data to accuracy consistent well with the measurements are given. The zero material dispersion-wavelength (ZMDW) and group velocity are also determined using the refractive index data. The Fermi level is calculated exploiting the extinction coefficient dispersion curves. The absorption coefficient, both direct and indirect optical energy gaps, and Urbach energy are evaluated using the absorption edge calculations. The different factors that play a role for controlling the refractive indices such as coordination number, electronic polarizability, field strength of cations, bridging and nonbridging oxygen, and optical basicity are discussed in accordance with the obtained index data. IR spectroscopy is used as a structural probe of the nearest-neighbor environment in the glass network. 相似文献
17.
Eu3+-doped La2O3-3B2O3 crystal and glass were prepared by solid state reaction under different calcination temperature. The emission spectrum, phonon sideband (PSB), charge transfer band (C.T.B.) and lifetime of the Eu3+ ion in the two materials, with the same composition but with different phase, were investigated. With excitation at 394 nm light, the glass presented intense 618 nm red luminescence; however, the crystal gave 696 nm red luminescence. This difference is ascribed to the discrepancy of the local structure around the Eu3+ ion in the crystal and glass. To clarify the discrepancy, the coordination of Eu3+ in the borate glass and crystal was investigated. The results show that Eu3+ ions formed a complex Eu3+-O2−-B3+ bond in glass; however, in the crystal, it formed a complex Eu3+-O2−-La3+ bond. The lifetime of Eu3+ ions in the crystal and the glass is 3.08 ms and 1.98 ms, respectively. This indicates that the discrepancy in the local structure around the Eu3+ ions between the crystal and the glass leads to different fluorescence properties. 相似文献
18.
Y.N.Ch. Ravi Babu P. Sree Ram Naik K. Vijaya Kumar N. Rajesh Kumar A. Suresh Kumar 《Journal of Quantitative Spectroscopy & Radiative Transfer》2012,113(13):1669-1675
The multicomponent lead bismuth magnesium borophosphate glass systems (LBMBPS) doped with Samarium ions with the molar compositions of (50?x)PbOxBi2O325MgHPO424B2O31Sm2O3 (where x=10, 20, 30, and 40) were fabricated using conventional melt quenching technique. The amorphous nature of these glass samples was confirmed with XRD studies. The spectral data from the optical absorption studies were employed to compute various spectroscopic parameters such as Judd–Ofelt intensity parameters. The Judd–Ofelt parameterization employed reflects the covalency and vibration frequencies of the ligands with Samarium ions. The radiative parameters such as radiative transition probabilities (A), the total radiative transitional probabilities (AT), radiative life times (τR), branching ratios (β) and absorption cross sections (Σ) were computed for certain lasing levels. The glass systems thus developed indicate their potential lasing candidature. The emission cross sections (σE) for the significant lasing transitions 4G5/2→6H5/2, 4G5/2→6H7/2, and 4G5/2→6H9/2 evaluated from the photoluminescence spectra were reported. The radiative properties obtained in our investigations suggest their lasing candidature. 相似文献
19.
V.A. Fedorov Yu.N. Korkishko J.A. Sanz-García E. Cantelar R. Nevado G. Lifante F. Cussó 《Applied physics. B, Lasers and optics》2001,73(5-6):449-451
We report the dependence of the unit-cell parameters and the extraordinary and ordinary refractive indices of Er3+/Yb3+-codoped LiNbO3 crystals. Both properties depend in a non-monotonic manner on the Er3+/Yb3+ content. A singularity was observed at concentrations of 1.1-1.2 mol. % in the crystal (0.6-0.7 mol. % in the melt). In the
same way the Er and Yb concentration influences the periodically poled lithium niobate formation. The observed behavior of
refractive indices and unit-cell parameters of Er3+/Yb3+-codoped LiNbO3 crystals could be explained in terms of the RE3+-ion concentration affecting the Li-vacancy concentration and the RE3+-ion positions in the crystal.
Received: 21 May 2001 / Revised version: 22 August 2001 / Published online: 23 October 2001 相似文献
20.
Yasser Saleh Mustafa Alajerami Suhairul Hashim Wan Muhamad Saridan Wan Hassan Ahmad Termizi Ramli Azman Kasim 《Physica B: Condensed Matter》2012,407(13):2398-2403
Several studies showed the interesting properties of trivalent lanthanide ions when doped in various types of glasses. Optical and physical properties of lithium magnesium borate glasses doped with Dy3+ then with Sm3+ ions were determined by measuring their absorption and luminescence spectra in the visible region. The absorption spectra of Dy3+ showed eight absorption bands with hypersensitive transition at 1265 nm (6H15/2→6F11/2-6H9/2) and three PL emission bands at 588 nm (4F9/2→6H15/2), 660 nm (4F9/2→6H13/2) and 775 nm (4F9/2→6H11/2). Regarding the Sm3+, nine absorption bands were observed with hypersensitive transition at 1237 nm (6H5/2–6F7/2); the PL spectrum showed four prominent peaks at 4G5/2→6H5/2 (yellow color), 4G5/2→6H7/2 (bright orange color), 4G5/2→6H9/2 (orange reddish color) and 4G5/2→6H11/2 (red color), respectively. Finally, a series of physical parameters such as the oscillator strengths, refractive index, ions concentration, Polaron radius and other parameters were calculated for each dopant. 相似文献