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1.
We have demonstrated the continuous wave laser operation of Yb3+:YVO4. For Ti:Al2O3 laser pumping at 985 nm, a maximum slope efficiency of 41.1% and a threshold pump power of 76 mW were obtained. The maximum output power was 433 mW at a laser wavelength of 1037 nm.Using a cw diode laser around 974 nm as a pump source, a slope efficiency of 10.9% and a maximum output power of 152 mW were achieved at a laser wavelength of 1039 nm. The laser threshold pump power was 608 mW with respect to the absorbed pump power. The effective emission cross-sections for the 2F5/22F7/2 transition were determined using the Füchtbauer–Ladenburg equation. The maxima of the effective absorption and emission cross-sections were found at 984.5 nm (6.74×10-20 cm2) in -po larization and 985.5 nm (4.28×10-20 cm2) also in -p olarization. The upper laser level lifetime was measured with suppression of radiation trapping and is around 318 s. PACS 42.55.Rz; 42.55.Xi; 42.70.Hj 相似文献
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YVO4:Yb3+,Er3+; YVO4:Yb3+,Tm3+; and YVO4:Yb3+,Er3+,Tm3+ were all synthesized via sol-gel method with a subsequent thermal treatment. Specifically, YVO4:Yb3+,Er3+,Tm3+ phosphors were prepared with different annealing temperatures to study the influence of temperature. The transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray diffractometer (XRD), and photoluminescent (PL) spectrofluorometer were used to investigate the morphology, crystal structure, and up-conversion luminescent properties of all samples. In summary, all samples were granular-like nanoparticles and well crystallized with the same tetragonal phase as YVO4. Under the irradiation at 980 nm, YVO4:Yb3+,Er3+ phosphors can generate green emission at 525 and 553 nm and red emission at 657 nm, while YVO4:Yb3+,Tm3+ phosphors can generate blue emission at 476 nm, red emission at 648 nm, and near-infrared emission at 800 nm. Notably, YVO4:Yb3+,Er3+,Tm3+ samples can exhibit green emission, blue emission, red emission, and near-infrared emission at the same time, which might endow the as-prepared samples with potential applications in many fields, such as luminous paint, infrared detection, and biological label. 相似文献
5.
Lin Yanfeng Zhang Ge Zhu Haiyong Huang Chenghui Wei Yong 《Journal of Russian Laser Research》2008,29(6):520-525
An 2 μm pulse laser based on an intracavity optical parameter oscillator (OPO) pumped by an electrooptical Q-switched 1.064 μm laser is realized. A type-II phase-matched (θ = 51.5° and φ = 0) KTP crystal and a limiting diaphragm with a diameter of 4 mm were used. The parameters of the KTP-OPO tuning curves
as a function of the phase matching angles were analyzed for the case of 1.064 μm laser pumping. Experiments based on single and double KTPs for walk-off compensation were performed. An output energy of
26 mJ in the 2 μm wavelength region was obtained with a pump-to-signal conversion efficiency of 26%. The center wavelengths of the signal
and idle lights were 2165.4 and 2088.6 nm with a FWHM of 3.8 and 4 nm, respectively. 相似文献
6.
Z. Zhu J. Li A. Brenier G. Jia Z. You X. Lu B. Wu C. Tu 《Applied physics. B, Lasers and optics》2007,86(1):71-75
Yb3+:GdAl3(BO3)4 (hereafter Yb3+:GAB) crystals with large sizes and good optical quality have been grown by the top-seed solution growth (TSSG) method. The polarized absorption and emission spectra have been investigated at room temperature. For the σ-polarization, the intensities of both absorption and emission spectra are stronger than those for the π-polarization, the σ-absorption cross section of Yb3+ in GAB being 3.43×10-20 cm2 at 977 nm, and the σ-emission cross section being 0.98×10-20 cm2 at 1045 nm. The fluorescence lifetime of the 2
F
5/2→2
F
7/2 transition was measured to be 800 μs in the 5% doped sample used for our laser experiments, 993 μs in a 10% doped sample and 569 μs in a 0.5% doped sample. The laser parameters were estimated as: βmin=0.022, Isat=10.4 kW/cm2 and Imin=0.23 kW/cm2. About 0.4 W laseroutput at the wavelength of 1043 nm was achieved when the Yb3+:GAB crystal was pumped by a 974 nm laser diode, with 27.4% slope efficiency. PACS 42.55.-f; 42.70.Hj; 78.20.-e; 81.10.Dn 相似文献
7.
Hyppänen I Hölsä J Kankare J Lastusaari M Pihlgren L Soukka T 《Journal of fluorescence》2008,18(6):1029-1034
The up-converting ZrO2:Yb3+,Er3+ nanomaterials were prepared with the combustion and sol–gel methods. FT-IR spectroscopy was used for analyzing the impurities.
The crystal structures were characterized with X-ray powder diffraction and the mean crystallite sizes were estimated with
the Scherrer formula. Up-conversion luminescence measurements were made at room temperature with IR-laser excitation at 977 nm.
The IR spectra revealed the conventional and OH− impurities for the combustion synthesis products. The structure of the ZrO2:Yb3+, Er3+ nanomaterials was cubic except for the minor monoclinic and tetragonal impurities obtained with the sol–gel method. The materials
showed red (650–700 nm) and green (520–560 nm) up-conversion luminescence due to the 4F9/2→4I15/2 and (2H11/2, 4S3/2)→4I15/2 transitions of Er3+, respectively. The products obtained with the combustion synthesis exhibited the most intense luminescence intensity and
showed considerable afterglow. 相似文献
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Toshiyuki Abe Chongying Dong Haisheng Li 《Communications in Mathematical Physics》2005,253(1):171-219
The fusion rules for the vertex operator algebras M(1)+ (of any rank) and V+L (for any positive definite even lattice L) are determined completely.Supported by JSPS Research Fellowships for Young ScientistsPartially supported by NSF grants and a research grant from the Committee on Research, UC Santa CruzPartially supported by a NSA grant and a grant from Rutgers University Research Council 相似文献
10.
P. A. Popov P. P. Fedorov S. V. Kuznetsov V. A. Konyushkin V. V. Osiko T. T. Basiev 《Doklady Physics》2008,53(7):353-355
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The results of a theoretical study of quasi-phase matched processes at self-frequency conversion in the Q-switched regime are presented. A scheme containing a periodically poled active nonlinear crystal and an acousto-optical modulator inserted inside the cavity is considered. Solutions of the set of equations describing such scheme are obtained by numerical methods. The time dynamics of the self-frequency doubling, self-frequency summing, and self-parametric frequency conversion processes are studied in detail. The energy characteristics of the radiation are also calculated and compared with those in the stationary regime. 相似文献
13.
S. Ding P. Wang X. Qing J. Zhang S. Wang X. Zhang 《Applied physics. B, Lasers and optics》2011,104(4):819-827
The actively Q-switched solid-state yellow Raman laser with intracavity frequency doubling has attracted extensive research due to its high
efficiency, simplicity and compactness. In this paper, the normalized space-dependent rate equations of this kind of lasers
are deduced and analyzed to illustrate the effects of the composite variables on the yellow-laser performance, and several
general curves are generated. The optimized values of the composite parameters are analyzed for the efficient yellow-laser
output. In the end, application examples are given to shown that these theoretical results can predict the performance of
actively Q-switched intracavity frequency-doubled solid-state yellow Raman lasers effectively. 相似文献
14.
We have calculated the potential energy surfaces forN = Z,20Ne-112Ba nuclei in an axially deformed relativistic mean field approach. A quadratic constraint scheme is applied to determine the
complete energy surface for a wide range of the quadrupole deformation. The NL3, NL-RA1 and TM1 parameter sets are used. The
phenomenon of (multiple) shape coextistence is studied and the calculated ground and excited state binding energies, quadrupole
deformation parameters and root mean square (rms) charge radii are compared with the available experimental data and other
theoretical predictions. 相似文献
15.
S. V. Dmitriev N. N. Medvedev R. R. Mulyukov O. V. Pozhidaeva A. I. Potekaev M. D. Starostenkov 《Russian Physics Journal》2008,51(8):858-865
The possibility of existence of nonlinear localized vibrational modes in an A3B two-dimensional crystal with pairwise interatomic bonds is demonstrated. Such modes are easily realized when the difference
between masses of atoms A and B is significant and the spectrum of small-amplitude crystal vibrations has a sufficiently wide
gap. The influence of the uniform tension/compression deformation on the small-amplitude crystal vibration spectrum and on
the existence of nonlinear localized modes is investigated.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 73–79, August, 2008. 相似文献
16.
M. Eichhorn 《Applied physics. B, Lasers and optics》2008,93(4):773-778
Using high-spatial and -spectral brightness laser diodes, a resonantly pumped high-power continuous-wave (CW) Er3+:YAG laser with up to 9 W of output power could be realized. Due to the lower upconversion loss in the 0.5% Er3+-doped crystal, intrinsic efficiencies of up to 64.3% and an optimum outcoupling of ∼20% were found. The output power was
compared to quasi-three-level theory with good agreement. In an optimized cavity design a mode fill efficiency of ∼95% was
achieved. 相似文献
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N. Oshimo 《The European Physical Journal C - Particles and Fields》2005,39(3):383-388
The measurability of generation mixing is studied on pair production of sneutrinos in e
+
e
- collisions and their subsequent decays into two different charged leptons e and μ with two lighter charginos. The analyses are made systematically in a general framework of the supersymmetric extension
of the standard model. The production and decay process depends on the parameters of the chargino sector as well as those
of the sneutrino sector. Although generation-changing interactions are severely constrained by radiative charged-lepton decays,
sizable regions in the parameter space could still be explored at e
+
e
- colliders in the near future.
Received: 6 October 2004, Revised: 14 November 2004, Published online: 14 January 2005
PACS:
11.30.Hv, 12.15.Ff, 12.60.Jv, 14.80.Ly 相似文献
19.
T.-J. Wang J.-C. Gao Yu. M. Andreev S. A. Bereznaya T. N. Kopylova Z. V. Korotchenko G. V. Lanskii T. D. Malinovskaya A. N. Morozov S. Yu. Sarkisov 《Russian Physics Journal》2007,50(6):560-565
The most probable parameters of the pure, doped, and mixed GaSe1−xSx (x ≤ 0.4) crystals (solid solutions) are presented together with the results of investigations of their crystal structure
and defects, optical and mechanical properties, and damage thresholds.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 35–40, June, 2007. 相似文献
20.
A. Yu. Loginov 《Physics of Atomic Nuclei》2011,74(5):740-754
The (1 + 1)-dimensional nonlinear O(3) σ model involving an explicitly broken symmetry is considered. Sphalerons are known to exist in this model. These sphalerons
are of a topological origin and are embedded kinks of the sine-Gordon model. In the case of a compact spatial manifold S
1, sine-Gordon multikinks exist in the model. It is shown that the model admits a nonstatic generalization of the sine-Gordon
kink/multikink, Q kink/multikink. Explicit expressions are obtained for the dependence of the Q kink energy and charge on the phase frequency of rotation. The Q kink is studied for stability, and expressions are obtained for the eigenfunctions and eigenfrequencies of the operator of
quadratic fluctuations. It is shown that the Q kink is unstable over the entire admissible frequency range ω ∈ [−1, 1]. The one-loop quantum correction to the static-kink mass is calculated, and the Q-kink zero mode is quantized. It is shown that, in a general static case, the field equations of the model are integrable
in quadratures. 相似文献