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oe1(光电查) - 科学论文

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  • [IEEE 2019 Joint Conference of the IEEE International Frequency Control Symposium anEuropean Frequency and Time Forum (EFTF/IFC) - Orlando, FL, USA (2019.4.14-2019.4.18)] 2019 Joint Conference of the IEEE International Frequency Control Symposium and European Frequency and Time Forum (EFTF/IFC) - Ultrastable Laser System Using Room-Temperature Optical Cavity with 4.8??10 <sup>a??17</sup> Thermal Noise Limit

    摘要: A new clock laser system using an optical cavity with 4.8×10-17 thermal noise limit has been developed for rapid evaluation of ytterbium lattice clocks. This was realized by using a 30-cm-long ULE cavity, fused-silica mirror substrates, and crystalline mirror coatings. The frequency stability of the beating signal between the new clock laser and the old clock laser was limited by the latter. The linewidth and the frequency stability of the new clock laser will be measured by comparing the frequency between two similar systems.

    关键词: linewidth,ytterbium,optical lattice clock,frequency stability,optical cavity,clock laser,crystalline coating

    更新于2025-09-19 17:13:59

  • Thermo-optic and spectroscopic properties of Yb:GAGG, Nd:GAGG and Nd:GGG laser materials at cryogenic temperature

    摘要: The solid-state lasers provide an attractive approach to enhance the laser performance benefitting from significant improvements in both thermo-optic and spectroscopic properties of the gain mediums under cryogenic temperature. Here, thermo-optic properties of Yb:Gd3(AlxGa1-x)5O12 (Yb:GAGG) and Nd:Gd3(AlxGa1-x)5O12 (Nd:GAGG) laser crystals, including thermal conductivity (κ), thermal expansion coefficient (α) and specific heat at constant pressure (Cp) were measured from 77 to 298 K. In addition, the thermal shock resistance parameters were also calculated. The spectroscopic properties and the fluorescence lifetimes of laser gain mediums Yb:GAGG, Nd:GAGG and Nd:Gd3Ga5O12 (Nd:GGG) were characterized at 77, 150, 298 K. The stimulated emission cross sections of these laser materials were determined by use of the Füchtbauer-Ladenburg (FL) formula at each temperature.

    关键词: GGG,cryogenic cooling,GAGG,spectroscopic properties,thermal properties,Neodymium,Ytterbium

    更新于2025-09-19 17:13:59

  • [Laser Institute of America ICALEO? 2014: 33rd International Congress on Laser Materials Processing, Laser Microprocessing and Nanomanufacturing - San Diego, California, USA (October 19–23, 2014)] International Congress on Applications of Lasers & Electro-Optics - High power 1030 nm YB-doped picosecond all fiber laser

    摘要: A high power 1030 nm passively mode-locked ytterbium-doped picosecond fiber laser by master oscillator power amplifier (MOPA) configuration is demonstrated. The laser system consists of the picosecond seed and three stages of ytterbium-doped all-fiber amplifiers. The seed is mode-locked by a semiconductor saturable absorber mirror (SESAM), and a stable output is obtained with 30.7 ps pulse width, 29.0 MHz repetition rate, and 30 mW average output power. The laser operates at 1030.4 nm with a spectral width of 0.15 nm. After three stages of fiber amplification, the final output power is scaled up to 101 W in a 30/250 μm double-clad ytterbium doped fiber with the slope efficiency of 76.7%. The laser performance with the pulse width of 36.6 ps, pulse energy of 3.48 μJ, peak power as high as 97 kW operating at 1030.4 nm with bandwidth of 1.46 nm is achieved, and the beam quality M2 is 2.78.

    关键词: passively mode-locked,master oscillator power amplifier,lasers,ytterbium-doped fiber

    更新于2025-09-19 17:13:59

  • Graded‐Index Ytterbium‐Doped Optical Fiber Fabricated through Vapor Phase Chelate Delivery Technique

    摘要: Herein, the fabrication of ytterbium-doped graded refractive-index few-mode fiber (GRIN-FMF) is described for the first time following a vapor phase chelate delivery technique. Investigation is carried out to find out the best possible approach to fabricate the preform. The optimization of the process steps along with composition and associated process parameters leads to a parabolic refractive-index profile with a profile parameter of 2 in the developed fiber. A large core of 30 μm diameter and a low numerical aperture (NA) of 0.08 with graded distribution of dopant ions is achieved with a good repeatability. Amplification gain of more than 20 dB with good beam quality for pulses with kW peak power without any distortion in temporal, spectral, and spatial profile proves the potential of the fiber for many promising applications.

    关键词: preform fabrication,graded-index fibers,ytterbium,vapor phase chelate delivery,fiber lasers

    更新于2025-09-19 17:13:59

  • Tunable Q-switched ytterbium-doped fibre laser with Nickel Oxide saturable absorber

    摘要: A passively Q-switched ytterbium-doped fibre laser (YDFL) using a nickel oxide-based saturable absorber is proposed and demonstrated. The Q-switched YDFL is capable of generating a stable output with a minimum pulse width of 6.9 ls and maximum repetition rate of 57.01 kHz. The generated pulses are highly stable, with an observed signal-to-noise ratio of * 33 dB. The output of the laser can be tuned over a wavelength range of 18 nm from 1035 to 1053 nm. The Q-switched YDFL would find use in multiple applications ranging from medicine to manufacturing.

    关键词: Ytterbium-doped fibre laser,NiO saturable absorber,Q-switching

    更新于2025-09-19 17:13:59

  • Modeling of the 3D spatio-temporal thermal profile of joule-class -based laser amplifiers

    摘要: Thermal pro?le modi?cation of an active material in a laser ampli?er via optical pumping results in a change in the material’s refractive index, and causes thermal expansion and stress, eventually leading to spatial phase aberrations, or even permanent material damage. For this purpose, knowledge of the 3D spatio-temporal thermal pro?le, which can currently only be retrieved via numerical simulations, is critical for joule-class laser ampli?ers to reveal potentially dangerous thermal features within the pumped active materials. In this investigation, a detailed, spatio-temporal numerical simulation was constructed and tested for accuracy against surface thermal measurements of various end-pumped Yb3+-doped laser-active materials. The measurements and simulations show an excellent agreement and the model was successfully applied to a joule-class Yb3+-based ampli?er currently operating in the POLARIS laser system at the Friedrich-Schiller-University and Helmholtz-Institute Jena in Germany.

    关键词: diode-pumped solid-state lasers,ytterbium,laser ampli?ers,spatio-temporal thermal pro?le modeling,high intensity lasers

    更新于2025-09-19 17:13:59

  • [IEEE 2019 Photonics North (PN) - Quebec City, QC, Canada (2019.5.21-2019.5.23)] 2019 Photonics North (PN) - Dual-wavelength Yb:YAP laser

    摘要: Dual-wavelength operation of Yb:YAP laser with an intracavity birefringent filter (BRF) was demonstrated. By using a 1 mm-thick BRF, DW pairs with wavelength separation ranging from 1.8 nm up to 11.3 nm could be generated based on gain balancing provided by a single transmission peak of the filter. In this way, the wavelength separation was not limited by the available free spectral range of the filter.

    关键词: Diode-pumped lasers,Birefringence,ytterbium lasers

    更新于2025-09-16 10:30:52

  • [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) - Sub-20 fs ? 10.5 W Visible Pulse Generation from Yb-Doped Fiber Laser

    摘要: High-power high-repetition rate femtosecond ytterbium-doped fiber lasers offer new perspectives in femtochemistry, solid-state physics and strong field physics. In particular, high-order harmonic generation (HHG) driven by Yb-fiber laser has demonstrated high photons flux in extreme ultraviolet (XUV) spectral range [1,2]. Shortening the laser pulse improves the achievable time resolution in pump-probe experiments and also the efficiency and the spectral extent of HHG (cutoff wavelength). However, the gain bandwidth of the Yb:fiber limits the pulse duration in the 250 fs - 130 fs range. To solve this issue, nonlinear pulse compression experiments using Yb:fiber lasers have been carried out at the fundamental wavelength (1030 nm) to downscale the pulse duration in the 10 fs range [3,4]. On the other hand, so far the highest reported XUV photons flux up to milliwatt-class has been obtained at 515 nm driving wavelength with 11W - 85 fs pulses [5]. While frequency doubling an ultrashort (< 30 fs) pulse requires a trade-off between efficiency and pulse duration lengthening, we present in this work an efficient and high power sub-20 fs visible laser source based on the second harmonic generation (SHG) of a high energy Yb-doped femtosecond fiber laser followed by a nonlinear compression stage in a krypton-filled capillary.

    关键词: femtosecond ytterbium-doped fiber lasers,nonlinear pulse compression,krypton-filled capillary,second harmonic generation,high-order harmonic generation

    更新于2025-09-16 10:30:52

  • Enhancing Photovoltaic Performance of GaAs Single-Junction Solar Cells by Applying a Spectral Conversion Layer Containing Eu-Doped and Yb/Er-Doped Phosphors

    摘要: In this study, we examined e?orts to increase the photovoltaic performance of GaAs single-junction solar cells using spectral conversion layers, respectively, composed of europium-doped (Eu-doped) phosphors, ytterbium/erbium-doped (Yb/Er-doped) phosphors, and a combination of Eu-doped and Yb/Er-doped phosphors. Spin-on ?lm deposition was used to apply the conversion layers, all of which had a total phosphor concentration of 3 wt%. The chemical compositions of the phosphors were examined by energy-dispersive X-ray spectroscopy. The ?uorescence emissions of the phosphors were con?rmed by using photoluminescence measurements. Under laser diode excitation at 405 nm, we observed green luminescent downshift (LDS) emissions by Eu-doped phosphors at wavelengths of 479 nm to 557 nm, and under excitation at 980 nm, we observed red up-conversion (UC) emissions by Yb/Er-doped phosphors at wavelengths of 647 nm to 672 nm. The spectral conversion layers were characterized in terms of optical re?ectance, external quantum e?ciency, and photovoltaic current and voltage under AM 1.5 G simulations. The conversion e?ciency of the cell combining Eu-doped and Yb/Er-doped phosphors (23.84%) exceeded that of the cell coated with Yb/Er-doped phosphors (23.72%), the cell coated with Eu-doped phosphors (23.19%), and the cell coated without phosphors (22.91%).

    关键词: ytterbium/erbium-doped (Yb/Er-doped),europium-doped (Eu-doped),up-conversion,phosphors,GaAs solar cell,luminescent downshift

    更新于2025-09-16 10:30:52

  • On the development of a new approach to the design of lanthanide-based materials for solution-processed OLEDs

    摘要: The targeted design of lanthanide-based emitters for solution-processed organic light-emitting diodes (OLEDs) resulted in obtaining an NIR OLED with one of the highest efficiencies among ytterbium-based solution-processed OLEDs (30 μW W?1). The design was aimed at the combination of high luminescence efficiency with solubility and charge carrier mobility. The latter was achieved thanks to the introduction of the purposefully selected neutral ligands, which combine electron mobility and the ability to sensitize lanthanide luminescence. Besides, the HOMO and LUMO energies and charge carrier mobility of solution-processed thin films of coordination compounds were measured experimentally for the first time, and novel highly luminescent europium-based materials with PLQYs of up to 80% and purely NIR luminescent ytterbium complexes were obtained.

    关键词: NIR OLED,europium complexes,lanthanide-based materials,solution-processed OLEDs,ytterbium complexes

    更新于2025-09-16 10:30:52