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oe1(光电查) - 科学论文

32 条数据
?? 中文(中国)
  • Spectroscopic and laser properties of erbium and ytterbium co-doped photo-thermo-refractive glass

    摘要: Spectral-luminescent characteristics of erbium ions in photo-thermo-refractive (PTR) glasses doped with different concentrations of ytterbium and erbium oxides were investigated in this work. X-ray diffraction pattern of studied glasses was carried out. Judd-Ofelt parameters of intensity Ωt were obtained and used for deriving emission cross-sections and radiative lifetimes. It was found that the peak emission cross-sections values at a wavelength of 1.53 μm obtained from F-L and McCumber methods are 0.59 × 10?20 cm2 and 0.60 × 10?20 cm2, respectively, which are very similar and compared with those of silicate glasses. A quite high value of quantum yield at the wavelength of 1.53 μm for the sample with 0.1 mol% Er2O3 co-doped with ytterbium oxide has been investigated. Energy transfer efficiency from ytterbium ions to erbium ones was found to be 80% and 86% for erbium- and 1 mol% and 2 mol% Yb2O3-co-doped PTR glass, respectively. Laser properties of 2Yb-01Er PTR glass were carried out. The gain spectrum starts to be positive when the population inversion parameter gets to 0.5. Laser action was demonstrated at room temperature. It was found that the round-trip losses of the Er/Yb-PTR element are 0.28%.

    关键词: Ytterbium,DFB laser,PTR glass,Erbium,XRD,Judd-ofelt

    更新于2025-09-23 15:19:57

  • Synthesis, structure and optical properties of Erbium-doped Lithium Barium Phosphate

    摘要: Li2BaP2O7 activated with Er3+ ions was prepared by the classic ceramic method and characterized by X-ray diffraction technique, IR, Raman and photoluminescence (PL) spectroscopies. The Li2BaP2O7: Er phosphors exhibited a monoclinic single phase structure with C2/c space group. A green and red emission lines dominate the spectrum upon excitation at 400 nm. The CIE-coordinate (x = 0.308, y = 0.512) were found in green light. Free ion parameters of the Er3+ ions in Li2BaP2O7 and the Judd–Ofelt parameters were calculated and they were used to explore the radiative parameters such as transition probability (AT), and branching ratios (β) related to the Er3+ emission transitions. The calculated 4S3/2 radiative life time around 0.198 ms is compared with the experimental value. The calculated quantum efficiency is about 42 %. Li2BaP2O7: Er can be considered as a novel green phosphor.

    关键词: Erbium,green phosphor,Judd-Ofelt theory,optical spectroscopy

    更新于2025-09-19 17:15:36

  • Near-infrared and upconversion luminescence of Tm3+ and Tm3+/Yb3+-doped oxyfluorosilicate glasses

    摘要: Oxyfluorosilicate glasses-doped with different concentrations of Tm3+ and Tm3+/Yb3+ ions have been synthesized and characterized their absorption, photoluminescence, luminescence decay and upconversion properties. The Judd-Ofelt intensity parameters have been obtained from the absorption spectrum of Tm3+ single-doped glass and are in turn used to calculate radiative properties such as transition probabilities, branching ratios and lifetimes for the fluorescent levels of Tm3+ ions. Visible and near-infrared emission spectra of Tm3+ and Tm3+/Yb3+-doped glasses have been measured under 473 nm laser excitation. The quenching of emission intensities at higher concentrations of Tm3+ ions has been found to be due to cross-relaxation mechanisms. The Tm3+/Yb3+ co-doped glasses show upconverted emissions under 975 nm laser excitation. The mechanism of upconversion has been explained based on the pump power dependence of upconversion luminescence. The results reveal that the co-doped glasses are promising for optical fiber amplifiers operating at the relatively low-loss wavelength regions.

    关键词: Glasses,Optical properties,1.2 μm emission,Upconversion,Judd-Ofelt theory,Tm3+ and Tm3+/Yb3+

    更新于2025-09-19 17:15:36

  • Application of Judd-Ofelt Theory Upon Chlofluorophosphate Glass Doped with Erbium

    摘要: A series of erbium doped glasses chlorofluorophosphates were prepared and characterized. The absorption spectra were analyzed to determine the Judd-Ofelt parameters. The optical performance of these doped glasses suggesting the relevance of these glasses for optical fiber/ wave guide lasers and optical amplifiers.

    关键词: and optical amplifier,rare earth,Judd-Ofelt parameters,glass doped,laser,erbium

    更新于2025-09-19 17:15:36

  • Rich reddish-orange emitting PBTNAPr glasses for laser applications

    摘要: Lead borate oxyfluoride glasses containing different amounts of PrF3 with composition PbO–B2O3–TeO2–NaF–AlF3-PrF3 were prepared and characterized for visible and fiber lasers. The amorphous phase and compositional analysis were carried out through powder X-ray diffraction and Fourier transform infrared spectra, respectively. Using the room temperature optical absorption spectra, the spectroscopic properties were determined applying the modified Judd-Ofelt theory. The photoluminescence excitation spectral studies obtained by controlling the emission through Pr3+: 1D2 → 3H4 (604 nm) transition shows prominent excitation band positioned at ~448 nm (3H4 → 3P2). Upon 448 nm excitation, the studied glasses exhibit an intense emission through 1D2 → 3H4 (604 nm) transition along with feeble emissions from 3P1 and 3P0 metastable levels to the inner energy levels. The emission spectra show a shift towards longer wavelengths (called the red-shift) with increase of PrF3 content. The luminescence decay time of 1D2 emission level was found decreased with increase of PrF3 content. The quenching of decay time was assigned to the transfer of energy among the excited Pr3+ ions at relatively higher PrF3 contents. The experimental results show that the studied glasses with 0.1 mol% of PrF3 could be the suitable candidate to design rich reddish-orange emitting lasers.

    关键词: Solid state lasers,Photoluminescence,Judd-Ofelt analysis,Lead borate glasses

    更新于2025-09-19 17:13:59

  • Comparative impact of Nd3+ ion doping concentration on near-infrared laser emission in lead borate glassy materials

    摘要: Different concentrations (0.2-1.0 mol%) of Nd3+ doped lead borate glass (LB) systems were prepared by melt quenching technique and have been studied using XRD and optical studies. Based on the calculations of Judd-Ofelt (J-O) theory derived from the optical absorption spectra, three J-O parameters have been obtained. Various radiative parameters (such as radiative transition probability (Arad), branching ratio (βcal), absorption cross-sections (Σ), radiative lifetime (τR) and etc., have been predicted through J-O parameters. Luminescence spectra were measured for all the samples. It has been observed that luminesce intensity gradually increased up to 0.8 mol % of Nd3+ and further increase in concentrations causes that the luminescence spectral intensity falls. This is proposed due to the concentration quenching of neodymium ions in the LB glass system. LB glass system with 0.8 mol % is found to be most intensive one in emission at 1.06 μm related to 4F3/2→4I11/2 in near infrared (NIR) transition.

    关键词: Absorption,emission cross-section,Photoluminescence,Judd-Ofelt,Lead borate glasses

    更新于2025-09-19 17:13:59

  • Synthesis and Luminescence properties of Lithium Aluminium Phosphate Glasses Doped with Nd <sup>3+</sup> Ion for Laser Medium

    摘要: Nd3+ ion doped lithium aluminium phosphate glasses were synthesized and studied their properties for laser medium application. The density and the refractive index of the glass samples were carried out at the room temperature. The optical and luminescence properties were studied by investigating absorption and NIR emission spectra of the glass samples. The glasses absorbed photons in ultraviolet (UV), visible light (VIS) and near-infrared (NIR) regions are clearly observed from absorption spectra. For the photoluminescence properties, the glass samples showed the strongest emission at 1063 nm when it were excited by 581 nm which assigned to the energy transitions of Nd3+. The three phenomenological Judd-Ofelt parameters (?2, ?4, ?6) were determined from the spectral intensities of absorption band in order to calculate the radiative transition possibility (AR), stimulated emission cross section (σ(?p)) and branching ratio (?R) of the 4F3/2?4I9/2, 4I11/2 and 4I13/2 transitions. From the obtained results the conclusions made about the possibility of using these glasses as laser material.

    关键词: luminescence properties,laser medium,lithium aluminium phosphate glasses,Nd3+ ion,Judd-Ofelt parameters

    更新于2025-09-19 17:13:59

  • Enhancement of Emission Intensity in Dy <sup>3+</sup> -Doped ZnO/ZnF <sub/>2</sub> Phosphoborate Glasses for W-LED Materials

    摘要: Presently, white light emitting diodes (W-LEDs) were be used to substitute for conventional incandescent and fluorescent lamps due to their advantages; thus, it gets attention to create Dy3+-doped zinc phosphoborate glasses for enhancing better lightness. In this research, the replacing of ZnO by ZnF2 in 49B2O3:30P2O5:(20-x)ZnO:xZnF2:1Dy2O3 glasses, 0 ≤ x ≤ 20 mol% were prepared by melt quenching method and investigated through optical absorption and photoluminescence properties. The absorption results can be used for calculating the Judd-Ofelt (JO) intensity parameters (Ωλ, λ = 2, 4 and 6) and led to predicting the stimulated emission in present glasses. The trend of JO parameters is found to be Ω2 > Ω4 > Ω6 for all glasses. Nevertheless, replacing of ZnF2 does not affect position and intensity of optical absorption of Dy3+-doped glasses, whereas the observed blue (481 nm), yellow (573 nm) and red (662 and 752 nm) emission intensities of photoluminescence spectra rise with ZnF2 contents; the emission intensity at 573 nm for 20ZnF2 show the highest and was higher than 20ZnO around 1.6 times. The emission color of Dy3+-doped zinc phosphoborate glasses has been evaluated with CIE 1931 chromaticity diagram. The results revealed that all glasses emit white light. Hence, these glasses may be suitable candidate for using in W-LED and lighting materials.

    关键词: optical absorption,Judd-Ofelt parameters,photoluminescence,ZnF2,W-LEDs,zinc phosphoborate glasses,Dy3+-doped

    更新于2025-09-19 17:13:59

  • Synthesis of intense red light-emitting β-Ca2SiO4:Eu3+ phosphors for near UV-excited light-emitting diodes utilizing agro-food waste materials

    摘要: The sugarcane baggage ash and chicken shells are the abundant by-products of agro-food waste materials. These waste materials have hazardous impact on environment and thus require proper utilization to get valuable products. The present report is a detailed study to use these materials to fabricate intense red light-emitting Eu-doped Ca2SiO4 (C2S) phosphors via conventional solid-state method. For this purpose, silica (SiO2) is extracted from sugarcane baggage ash at 600 °C via alkali extraction followed by acid precipitation method. The raw eggshells were washed, dried, and calcined in furnace at 900 °C in order to get calcium oxide (CaO). The structural, morphological, elemental, optical, and luminescent properties were characterized via X-ray diffraction, scanning electron microscopy, energy dispersed X-ray spectroscopy, transmission electron microscopy, UV–Visible spectroscopy, Fourier transform infrared spectroscopy, and photoluminescence techniques. The effect of Eu concentration (0.1 to 0.5 mol%) on the structural, optical, and luminescent properties of Ca2SiO4 has been studied in detail. The agro-food waste-derived phosphors exhibited intense emission at 625 nm corresponding to 5D0 → 7F2 transitions of Eu3+ ions under near-UV light excitation at 393 nm. The quenching mechanism and type of energy transfer interactions involved are studied via Blasse and Dexter’s theory. The photometric parameters such as CIE coordinates, CCT values, and color purity are calculated from emission spectra. Judd–Ofelt (?4) and other spectral parameters (radiative rates, branching ratio, radiative lifetime, and radiative cross-sectional area) are calculated as a probe to investigate the luminescent environment of Eu3+ ions in the Ca2SiO4 host lattice. The present agro-food waste-derived phosphors are expected to be promising candidates for UV-excited white light-emitting diodes in solid-state lightning and optoelectronic devices.

    关键词: Judd–Ofelt theory,Ca2SiO4:Eu3+,Agro-food waste,Luminescence,Phosphors

    更新于2025-09-16 10:30:52

  • Nd <sup>3+</sup> Doped In Zinc Barium Tellurite Oxyfluoride Glasses For Laser Application

    摘要: The tellurite glasses doped with Nd3+ ion were prepared with the compositions (55-x)TeO2-10ZnF2-35BaO-xNd2O3 (where x = 0.00, 0.05, 0.10, 0.50 1.00 and 1.50 mol%) by the normal melt quenching technique and characterized the spectroscopic properties. The spectroscopic properties of tellurite glasses measured from the absorption and emission measurements with Judd-Ofelt analysis. The X-ray diffraction (XRD) pattern confirms the amorphous nature. UV-Vis-NIR absorption spectra of tellurite glasses divulged nine significant peaks. The absorption peaks slightly increase with increasing of Nd3+ concentration. The NIR emission spectra at 913, 1,069 and 1,341 nm have been registered for Nd3+ in tellurite glasses, which corresponds to the transitions originating from 4F3/2 level to the 4I9/2, 4I11/2 and 4I13/2 levels of Nd3+ ion, respectively, under the excitation of 523 nm. The results indicate that the prepared glass system could be a suitable candidate for using it as laser gain media around 1,069 nm.

    关键词: Nd3+ ion,Judd-Ofelt analysis,tellurite glasses

    更新于2025-09-16 10:30:52