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11.
Kazamias S Douillet D Weihe F Valentin C Rousse A Sebban S Grillon G Augé F Hulin D Balcou P 《Physical review letters》2003,90(19):193901
We investigate the relevance of the absorption limit concept in the optimization of high harmonic generation. Thanks to the first direct observation of the coherence length of the process from high-contrast Maker fringes, we unravel experimental conditions for which the harmonic dipole response is enhanced when phase matching is realized within the absorption limit, leading to record conversion efficiencies in argon. Moreover, we show that harmonic generation in guided or freely propagating geometries are equivalent in the loose focusing regime. This analysis is generalized to other advanced phase-matching schemes, thereby predicting the possibility to boost the conversion efficiencies using light noble gases. 相似文献
12.
Aleksey Tyazhev Georgi Marchev Valeriy Badikov Adolfo Esteban‐Martin Dmitrii Badikov Vladimir Panyutin Galina Shevyrdyaeva Svetlana Sheina Anna Fintisova Valentin Petrov 《Laser \u0026amp; Photonics Reviews》2013,7(4):L21-L24
The defect chalcopyrite crystal HgGa2S4 has been employed in a 1064‐nm pumped optical parametric oscillator operating at 100 Hz, to generate ∼5 ns long idler pulses near 4 µm with energies as high as 6.1 mJ and average power of 610 mW. At crystal dimensions comparable to those available for the commercial AgGaS2 crystal, operation of the 1064‐nm pumped HgGa2S4 OPO is characterized by much lower pump threshold and higher conversion efficiency, with the most important consequence that such a device might become practical at pump levels sufficiently lower than the optical damage threshold. 相似文献
13.
P. D. Harty I. J. D. MacGregor P. Grabmayr J. Ahrens J. R. M. Annand I. Anthony R. Beck D. Branford G. E. Cross T. Davinson S. J. Hall T. Hehl J. D. Kellie T. Lamparter J. A. MacKenzie J. C. McGeorge G. J. Miller R. O. Owens M. Sauer R. Schneider K. Spaeth 《Physics letters. [Part B]》1996,380(3-4):247-252
The 12C(γ,pn) and 12C(γ,pp) reactions have been studied using tagged photons of energy Eγ = 150–400 MeV. Recoil momentum distributions are compared to the results of Monte Carlo calculations based on a two-nucleon photon absorption model and two different phase space models. The 12C(γ,pn) data at low missing energy are consistent with absorption on 1p2 and 1s1p nucleon pairs. 相似文献
14.
A. Perrin J.-M. Flaud A. Valentin C. Camy-Peyret H. Gbaguidi 《Journal of Molecular Spectroscopy》2000,200(2)
Using 0.002 cm−1 resolution Fourier transform absorption spectra of an 17O-enriched ozone sample, an extensive analysis of the ν3 band together with a partial identification of the ν1 band of the 17O16O17O isotopomer of ozone has been performed for the first time. As for other C2v-type ozone isotopomers [J.-M. Flaud and R. Bacis, Spectrochim. Acta, Part A 54, 3–16 (1998)], the (001) rotational levels are involved in a Coriolis-type resonance with the levels of the (100) vibrational state. The experimental rotational levels of the (001) and (100) vibrational states have been satisfactorily reproduced using a Hamiltonian matrix which takes into account the observed rovibrational resonances. In this way precise vibrational energies and rotational and coupling constants were deduced and the following band centers ν0(ν3) = 1030.0946 cm−1 and ν0(ν1) = 1086.7490 cm−1 were obtained for the ν3 and ν1 bands, respectively. 相似文献
15.
B. Krusche J. Ahrens R. Beck M. Fuchs S.J. Hall F. Härter J.D. Kellie V. Metag M. Röbig-Landau H. Ströher 《The European Physical Journal A - Hadrons and Nuclei》1999,6(3):309-324
Photoproduction of neutral pions from the deuteron has been studied for incident photon energies from 200 MeV to 792 MeV
with the TAPS detector at the Mainz MAMI accelerator. Total and differential cross sections covering the full angular range
have been obtained for coherent and incoherent single πo-photoproduction. Good agreement between model predictions and the data was found for the coherent process. The incoherent
cross section in the energy region of the Δ(1232)-resonance is overestimated by existing models. A comparison to model predictions
indicates that final state interaction effects are much more important than for the coherent reaction. However, the angular
dependence of the data in the Δ-peak region follows the pattern expected from the dominant excitation of the M1+-multipole on the free nucleon. The energy and angular dependence of single πo-photoproduction in the second resonance region is remarkably different from the reaction on the free proton, indicating a
strong nuclear effect. Finally the total cross section for double πo-photoproduction from the deuteron has been measured for the first time and was used to estimate the cross section for double
πo-photoproduction from the neutron.
Received: 24 June 1999 / Revised version: 30 August 1999 相似文献
16.
C. Saragovi F. Labenski de Kanter L. Kleiman R. Valentin C. Puglisi 《Hyperfine Interactions》1990,57(1-4):2285-2290
Several natural biotite samples were studied by M.E., electron microprobe and XRD. The M.E. parameters allow to group them
as oxybiotites, normal biotites, chloritized biotites and muscovitized biotites. Mechanisms of oxybiotite formation and processes
undergone by the rocks are discussed. 相似文献
17.
Valentin Roussellet Xiaodong Niu Hiroshi Yamaguchi & Fré dé ric Magoulé s 《advances in applied mathematics and mechanics.》2011,3(1):121-130
In this article, natural convection of a temperature-sensitive magnetic fluid
in a porous media is studied numerically by using lattice Boltzmann method. Results
show that the heat transfer decreases when the ball numbers increase. When the
magnetic field is increased, the heat transfer is enhanced; however, the average
wall Nusselt number increases at small ball numbers but decreases at large ball
numbers due to the induced flow being more likely confined near the bottom walls
with a high number of obstacles. 相似文献
18.
研究了三种掺Yb钒酸盐晶体Yb:LuVO4,Yb:YVO4和Yb:GdVO4的激光振荡中所呈现的光学双稳态效应.以晶体所吸收的抽运功率表征的双稳区宽度ΔPabs可超过1W,在双稳区高功率一侧的边界,即激光振荡的上阈值点,出现激光输出功率的不连续变化或跃变,同时发生亚毫秒时间尺度上的大幅度强度涨落.谐振腔的输出耦合透过率、晶体长度、晶体中的热效应等对双稳态效应均具有重要影响. 相似文献
19.
研究了三种掺Yb钒酸盐混晶Yb0.005:Y0.298Gd0.697VO4, Yb0.007:Y0.407Gd0.586VO4和Yb0.009:Y0.575Gd0.416VO4的室温偏振吸收谱和发射谱. 结果表明,最强的吸收和发射相应于π偏振,位
关键词:
掺Yb钒酸盐混晶
吸收谱和发射谱
激光振荡
偏振态 相似文献