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oe1(光电查) - 科学论文

18 条数据
?? 中文(中国)
  • Controlling multiphoton excited energy transfer from Tm <sup>3+</sup> to Yb <sup>3+</sup> ions by a phase-shaped femtosecond laser field

    摘要: The ability to control the energy transfer in rare-earth ion-doped luminescent materials is very important for various related application areas such as color display, bio-labeling, and new light sources. Here, a phase-shaped femtosecond laser field is first proposed to control the transfer of multiphoton excited energy from Tm3+ to Yb3+ ions in co-doped glass ceramics. Tm3+ ions are first sensitized by femtosecond laser-induced multiphoton absorption, and then a highly efficient energy transfer occurs between the highly excited state Tm3+ sensitizers and the ground-state Yb3+ activators. The laser peak intensity and polarization dependences of the laser-induced luminescence intensities are shown to serve as proof of the multiphoton excited energy transfer pathway. The efficiency of the multiphoton excited energy transfer can be efficiently enhanced or completely suppressed by optimizing the spectral phase of the femtosecond laser with a feedback control strategy based on a genetic algorithm. A (1 + 2) resonance-mediated three-photon excitation model is presented to explain the experimental observations. This study provides a new way to induce and control the energy transfer in rare-earth ion-doped luminescent materials, and should have a positive contribution to the development of related applications.

    关键词: energy transfer,rare-earth ions,femtosecond laser,luminescent materials,multiphoton absorption

    更新于2025-09-12 10:27:22

  • [IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - UV Luminescence in Ho:ZBLAN Glasses

    摘要: Compact, short-wavelength lasers are continuously considered as one of the most attractive among all coherent light sources. A very wide range of applications such as data storage, photolithography, medical diagnostics and sterilization motivates research and development on new active materials which can efficiently emit light in the UV spectral range. There are three general methods to achieve UV and visible light emission. The first are semiconductor-based LEDs and laser diodes - in the recent years a rapid progress in the field of semiconductor lasers has been observed resulting in a variety of commercially available short-wavelength laser diodes. These impressive devices, however, are not free from some disadvantages, like poor quality of the beam and limited output power. That’s why other sources continue to attract researchers’ attention. The second method deploys nonlinear crystals, which enable obtaining short wavelength emission by the frequency multiplication. The third way to achieve UV and visible light is to directly use the optical transitions within rare earth ions in solid state media [1-2]. This work is focused on this last method.

    关键词: short-wavelength emission,Ho:ZBLAN glasses,optical spectroscopy,rare earth ions,UV luminescence

    更新于2025-09-11 14:15:04

  • Investigation of luminescence mechanism of Nd3+-doped calcium aluminate glasses: Effect of glass-formers

    摘要: The relationship between the luminescence properties and the glass structure of Nd3+-doped CaO-Al2O3-(B2O3, SiO2, or Ga2O3) glasses are investigated. The luminescence properties of CaO-Al2O3-B2O3 system are twice as much as that of the CaO-Al2O3-(SiO2 or Ga2O3) system. The glass structure and the coordination environment of the Nd3+ ions were investigated using nuclear magnetic resonance, Raman and electron paramagnetic resonance spectroscopy. All Al, Ga, and Si atoms are four coordinated. The B atoms have three- and four-coordinated boron units, however, most of them are three coordinated. The hyper?ne sublevel correlation spectra reveal that the Al and B nuclei are in the coordination sphere of Nd3+ ions for aluminoborate glasses; however, only 27Al signals could be observed for aluminosilicate and aluminogallate glasses. Owing to the increased number of AlO4-BO3 connections and 11B nuclei around the Nd3+ ions, B has a signi?cant e?ect on the luminescence properties of the Nd3+ ions. The increase in GaO4 or SiO4 does not change the three dimensional-tetrahedral network, and the coordination environment of Nd3+ ions varies slightly. Thus, the e?ect of Ga2O3 and SiO2 on the luminescence properties of the Nd3+ ions is not as great as that of B2O3.

    关键词: Glass structure,Local environments of rare-earth ions,EPR,Luminescence properties,NMR

    更新于2025-09-10 09:29:36

  • Encyclopedia of Spectroscopy and Spectrometry || Optical Spectroscopy of Rare-Earth Ions in the Solid State

    摘要: The birth of optical spectroscopy as science can be considered from the time when in 1672 Isaac Newton published his famous paper describing the results of experiments where, using a glass prism, he decomposed a beam of sunlight into its optical spectral components ranging from blue to red. Since that time, scientists and engineers studied a broad range of phenomena associated with the interaction of light with matter, using the fact that light actually contains different spectral components. Within a field of optical spectroscopy, it is hard to underestimate the importance of optical spectroscopy of different optical centers in solid-state materials because of numerous scientific and industrial applications of such optical systems. These applications range from studying fundamental properties of impurity centers in solids, solid-state material properties, up-conversion devices, scintillators, and Faraday rotators to a creation of solid-state lasers.

    关键词: rare-earth ions,Fu¨chtbauer–Ladenburg theory,optical spectroscopy,Judd–Ofelt theory,McCumber theory,electron–phonon coupling,Franck–Condon principle,solid state

    更新于2025-09-10 09:29:36

  • Plasmon-enhanced upconversion photoluminescence: mechanism and application

    摘要: The enhanced local electromagnetic field (EM) excited on the noble metallic nanostructure exhibits potential application in various areas, particularly in surface-enhanced spectroscopy (SES). Resonant coupling of SPs to luminous centers can strongly moderate the emission spectra properties, including the angular distribution, the intensity, the speed of radiative decay, and even the spectrum radiation polarization, or so-called plasmon-enhanced fluorescence (PEF). Due to the low efficiency of emission and small absorption section of rare earth ions, plasmon-enhanced upconversion photoluminescence(PUCPL) has attracted increasing attention recently. In this review, we focus on recent advanced reports on PUCPL. First, the mechanism of the conventional upconversion process and related reports will be introduced. We will then demonstrate that the introduction of plasmonic nanostructure, including nonperiodic and periodic metallic nanostructures, has a critical effect on upconversion nanoparticles(UCNPs). The recent advances in plasmon-enhanced fluorescence with metallic tip configuration are also noted. Finally, the recent applications of PUCPL are introduced. As a result, the combination of a rare-earth luminescent center with plasmonic nanostructure can largely expand the application of upconversion materials.

    关键词: surface-enhanced spectroscopy,mechanism,plasmonic nanostructure,Plasmon-enhanced upconversion photoluminescence,application,rare earth ions

    更新于2025-09-10 09:29:36

  • Influence of the Tb3+ concentration on the luminescent properties of high silica glass

    摘要: Tb3+- doped high silica glass was prepared by sintering porous glass. The density, valence state and amount of Tb, transmittance, photoexcitation spectra, photoluminescence spectra, and cathodoluminescence spectra (CL) were recorded and the luminescence decay kinetics analyzed in details. These results show that the doping concentration in high silica glass is in direct proportion to the concentration in solution, and the density increases with the increasing concentration of rare earth ions as well as the intensity of emission spectrum. The largest emission intensity of 0.2 mol/L is more than 2 times higher than the intensity of the 0.05 mol/L. Besides, the “red” shift phenomenon could be distinguished clearly in the transmittance spectra. There is a broad band at the “red” region in the CL spectra. The decay time which is in the millisecond range in di?erent spectral range were measured and analyzed revealing that the decay time of 5D3 is shorter than that of 5D4.

    关键词: Luminescent properties,Rare earth ions,High silica porous glass

    更新于2025-09-10 09:29:36

  • Efficient improvement of 2.7μm luminescence of Er3+:oxyfluorideglass containing gallium by Yb3+ions codoping

    摘要: Mid-infrared laser materials with low phonon energy have significant applications. However, the development of available glass systems for high-power laser gain medium have posed a great challenge. Therefore, we investigated the 2.7 μm spectroscopic properties of Er3+/Yb3+-codopedoxyfluoride glass containing gallium, which were prepared by typically melting and quenching methods. The 2.7 μm luminescence properties of the Er3+/Yb3+-codopedoxyfluoride glass containing gallium were recorded by a 980 nm laser diode. The Judd–Ofelt parameters, decay curves, emission cross section, energy transfer efficiency, and quantum efficiency were calculated. The maximum emission cross section of YbFGa-0.5 is 1.63×10?20 cm2 by 980 nm excitation. The energy transfer efficiency is calculated to be 77.8% for the YbFGa-0.5 glass around 2700 nm. The quantum efficiency at 1530 nm is 65.6%. The resulting reveals that the best doping concentration ratio of Er3+:Yb3+ ions is 1:0.5, and suggests an effective energy transfer from Yb3+ to Er3+ ions.

    关键词: optical materials,rare-earth ions doped,optical spectroscopy,mid-infrared,energy transfer

    更新于2025-09-09 09:28:46

  • Up-conversion luminescence of RE3+ -doped polymer composites KGd(WO4)2&PMMA

    摘要: Poly(methyl methacrylate) (PMMA)-based luminescent materials are of prime interest for many new optoelectronic devices. This work presents the spectroscopic properties of PMMA-based composites containing KGd(WO4)2:Yb3+/Er3+/Tm3+, KGd(WO4)2:Yb3+/Tm3+ and KGd(WO4)2:Yb3+/Er3+ powders. These systems exhibit effective multicolor up-conversion luminescence in VIS and NIR spectral range under 980 nm excitation. The vibrational properties of the composites were investigated for the first time using the μ-Raman spectroscopy. The obtained results suggest that the KGd(WO4)2:Yb3+/Er3+/Tm3+&PMMA integrated system can be successfully used as a new phosphor for the up-conversion based optoelectronic devices.

    关键词: Micro-crystals,Rare earth ions,PMMA,KGd(WO4)2,Composites,Up-conversion

    更新于2025-09-04 15:30:14