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41.
N. A. Inogamov A. Ya. Faenov V. V. Zhakhovskii I. Yu. Skobelev V. A. Khokhlov Y. Kato M. Tanaka T. A. Pikuz M. Kishimoto M. Ishino M. Nishikino Y. Fukuda S. V. Bulanov T. Kawachi Yu. V. Petrov S. I. Anisimov V. E. Fortov 《等离子体物理论文集》2011,51(4):361-366
Laser‐matter interaction is defined by an electronic band structure of condensed matter and frequency ωL of electromagnetic radiation. In the range of moderate fluences, the energy absorbed by electrons from radiation finally thermalizes in the ion thermal energy. The thermalization processes are different for optical as compared with X‐ray quanta and for metals relative to semiconductors and dielectrics, since the light absorption and electron‐electron, electron‐ion dynamics are sensitive to the electron population in a conduction band and the width of a forbidden gap. Although the thermalization processes are different, the final state is simply a heated matter. Laser heating creates powerful stresses in a target if duration of a laser pulse τL is short in acoustic time scale. Nucleation and material removal take place under such stresses. Such way of removal is called here the spallative ablation. Thus the spallative ablation is an ablation mechanism universally important for qualitatively different materials and quanta (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
42.
Characterizing localization properties of two spinless electrons in a one-dimensional Harper model with concurrence 下载免费PDF全文
By mapping the Fock space of many local fermionic modes isomorphically onto a many-qubit space and using the measure of concurrence, this paper studies numerically the mode entanglement of two spinless electrons with on-site interaction U moving in the one-dimensional Harper model. Generally speaking, for electrons in extended regimes (potential parameter λ 〈 2), the spectrum-averaged concurrence N(C) first decreases slowly as A increases until its local minimum, then increases with λ until its peak at λ = 2, while for electrons in localized regimes (λ 〉 2), N(C) decreases drastically as λ increases. The functions of N(C) versus λ are different for electrons in extended and localized regimes. The maximum of N(C) occurs at the point λ= 2, which is the critical value in the one-dimensional singleparticle Harper model. From these studies it can distinguish extended, localized and critical regimes for the two-particle system. It is also found for the same λ that the interaction U always induce the decreases of concurrence, i.e., the concurrence can reflect the localization effect due to the interaction. All these provide us a new quantity to understand the localization properties of eigenstates of two interacting particles. 相似文献
43.
By means of a new Monte Carlo sampling of a grand canonical ensemble, we verify universality for the critical exponents and of two models of lattice trees constrained to be self-avoiding on sites or on bonds. The attrition constants are also obtained. This algorithm, a generalization of that recently proposed by Berretti and Sokal for random walks, appears to optimize the critical slowing down in the scaling region. Systematic and statistical errors are carefully estimated. 相似文献
44.
This paper derives explicit expressions for the propagation of Gaussian beams carrying two vortices of equal charges m=±1 diffracted at a half-plane screen, which enables the study of the dynamic evolution of vortices in the diffraction field. It shows that there may be no vortices, a pair or several pairs of vortices of opposite charges m=+1, -1 in the diffraction field. Pair creation, annihilation and motion of vortices may appear upon propagation. The off-axis distance additionally affects the evolutionary behaviour. In the process the total topological charge is equal to zero, which is unequal to that of the vortex beam at the source plane. A comparison with the free-space propagation of two vortices of equal charges and a further extension are made. 相似文献
45.
郑永树 《应用数学和力学(英文版)》1981,2(5):613-623
In this paper we discuss singular perturbations of first boundary value problem for higher order elliptic equations of two parameter and obtain the asymptotic expression for the formal solution containing two-parameter as well as the estimation of its remainder term. These results are the extensions of (2) and (3). 相似文献
46.
Investigations of two-phase heat transfer in the saturated flow-boiling region for multi-component mixtures has led to a proposed new correlation for the heat transfer coefficient where heat transfer of boiling is simply expressed in terms of the boiling number. This correlation was tested against the existing data on forced convective boiling heat transfer reported in the literature, giving satisfactory results; the correlation should, however, be tested further against wider data on convective heat transfer coefficients in multicomponent systems. The present lack of such data should be remedied. 相似文献
47.
48.
非同轴双束激光产生的等离子体辐射 总被引:1,自引:0,他引:1
采用非同轴双束激光,可得到时空差可控的二束不同性质的等离子体,实现在绝对同等条件下研究多束等离子体辐射的空间非均匀性和等离子体喷射对线加宽的影响。实验结果显示出在最简单的实验装置上实现等离子体强X射线泵浦X射线激光方案的可能性。 相似文献
49.
三维内肋管内插入螺旋扭带的强化传热实验 总被引:4,自引:0,他引:4
本文分别以水和乙二醇为工质,在Re数范围为:600~40000,Pr数范围为:5.5~110之间,对四根分别插入三种不同扭率螺旋扭带的三维内助管内的换热和流阻特性进行了实验研究。结果表明:三维内肋管内加装扭带的强化传热技术适用于低Re数下高Pr数工质的管内对流换热强化。根据实验值得到了流阻和换热关联式。 相似文献
50.
M. Yamanaka Y. Takeda S. Tanigawa A. Nishizawa N. Noda J. Fujita M. Takai M. Shimobayashi Y. Hayashi T. Koizumi K. Nagasaka S. Okajima Y. Tsunawaki A. Nagashima 《International Journal of Infrared and Millimeter Waves》1980,1(1):57-76
A twin optically-pumped far-infrared CH3OH laser has been constructed for use in plasma diagnostics. The antisymmetric doublet due to the Raman-type resonant two-photon transition is reproducibly observed at 118.8 m. With the 118.8-m line, it is obtained from the frequency separation of the anti-symmetric doublet that CH3OH absorption line center is 16±1 MHz higher than the pump 9.7-m P(36) CO2 laser line center. It is shown that the Raman-type resonant two-photon transition is useful in order to get several-MHz phase modulation for the far-infrared laser interferometer. Some preliminary performances of this twin laser for the modulated interferometer are described.This work was carried out under the collaborating research program at the Institute of Plasma Physics, Nagoya University, Nagoya 464, Japan. 相似文献