The single ionization rate of the diatomic molecular ion H2^+ with different active orbitals in an intense field is studied by using S-matrix theory. Our results show that the orientation-dependent single ionization ...
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The single ionization rate of the diatomic molecular ion H2^+ with different active orbitals in an intense field is studied by using S-matrix theory. Our results show that the orientation-dependent single ionization probability of H2^+ is greatly dependent on the symmetry and the electron density distribution of its initial states, and it can be used to identify the excited state of the molecular ion in the dissociation process.
A common failure mechanism in metallic thin-film interconnects is void propagation driven by electric fields and thermomechanical stresses. In this paper, a multiscale computational analysis is presented for predictiv...
A common failure mechanism in metallic thin-film interconnects is void propagation driven by electric fields and thermomechanical stresses. In this paper, a multiscale computational analysis is presented for predictive modeling of transgranular void dynamics. The modeling approach is hierarchical and involves atomistic simulations for property database development, molecular-dynamics simulations for understanding of void-tip mechanisms, and self-consistent mesoscopic simulations based on boundary-element methods and techniques for moving boundary propagation. An extremely rich void dynamical behavior is predicted, which includes faceting, facet selection, propagation of slits from the void surface, as well as formation of fine-scale crack-like features on the void surface, in agreement with recent experimental data.
The effect of the mesons σ* and Φ and the variety of UΣ(N )on the transition density of hyperon stars is examined within the framework of relativistic mean field theory for the baryon octet {n,p,Λ,Σ-,Σ0,Σ+,...
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The effect of the mesons σ* and Φ and the variety of UΣ(N )on the transition density of hyperon stars is examined within the framework of relativistic mean field theory for the baryon octet {n,p,Λ,Σ-,Σ0,Σ+,Ξand Ξ0} *** is found that,compared with that without considering the mesons σ* and Φ,the transition density of hyperon stars decreases,the critical baryon density that hyperons Σ-,Σ0,Σ+,Ξand Ξ0 appears to decrease too,but for Λ the effect is not *** U Σ(N )goes up,the critical baryon density of Σ+,Σ0 and Σincreases,that of Ξ0 decreases and that of Λ and Ξis *** addition,it is found that the variety of UΣ(N )almost does not influence the transition density.
A novel model reduction strategy for forced dissipative infinite-dimensional nonlinear dynamical systems is described. Unlike popular but empirical methods, this new approach does not require extensive data sets from ...
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作者:
A. Fratalocchi[]PRIMALIGHT
Faculty of Electrical Engineering Applied Mathematics and Computational Science
King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia and Department of Physics Sapienza University of Rome P.le A. Moro 2 I-00185 Rome Italy
I investigate the problem of finding a statistical description of a complex many-body system whose invariant measure cannot be constructed stemming from classical thermodynamics ensembles. By taking solitons as a refe...
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I investigate the problem of finding a statistical description of a complex many-body system whose invariant measure cannot be constructed stemming from classical thermodynamics ensembles. By taking solitons as a reference system and by employing a general formalism based on the Ablowitz-Kaup-Newell-Segur scheme, I demonstrate how to build an invariant measure and, within a one-dimensional phase space, how to develop a suitable thermodynamics. A detailed example is provided with a universal model of wave propagation, with reference to a transparent potential sustaining gray solitons. The system shows a rich thermodynamic scenario, with a free-energy landscape supporting phase transitions and controllable emergent properties. I finally discuss the origin of such behavior, trying to identify common denominators in the area of complex dynamics.
This paper reports on new experimental findings and conclusions regarding the pulsed-laser-induced melting-and-solidification behavior of PECVD a-Si films. The experimental findings reveal that, within the partial-mel...
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This paper reports on new experimental findings and conclusions regarding the pulsed-laser-induced melting-and-solidification behavior of PECVD a-Si films. The experimental findings reveal that, within the partial-melting regime, these a-Si films can melt and solidify in ways that are distinct from, and more complex than, those encountered in microcrystalline-cluster-rich LPCVD a-Si films. Specifically (1) spatially dispersed and temporally stochastic nucleation of crystalline solids occurring relatively effectively at the moving liquid-amorphous interface, (2) very defective crystal growth that leads to the formation of fine-grained Si proceeding, at least initially after the nucleation, at a sufficiently rapidly moving crystal solidification front, and (3) the propensity for local preferential remelting of the defective regions and grain boundaries (while the beam is still on) are identified as being some of the fundamental factors that can participate and affect how these PECVD films melt and solidify.
We demonstrate that high-order harmonic generation (HHG) with both high cutoff frequency and high conversion efficiency can be realized by using a Rydberg atom in a few-cycle laser pulse. This is because a Rydberg sta...
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We demonstrate that high-order harmonic generation (HHG) with both high cutoff frequency and high conversion efficiency can be realized by using a Rydberg atom in a few-cycle laser pulse. This is because a Rydberg state has a large electron orbital radius and small binding energy; therefore an electron in the Rydberg state can be ionized easily and accelerated directly toward the core under the interaction of a few-cycle laser pulse, leading to emission of harmonic photons. In this case, the tunneling process of the electron is not involved and, hence, the conversion efficiency and the cutoff frequency of harmonic generation can be higher than that predicted by the conventional three-step model.
In this paper we show that a flash lamp can be employed to induce controlled lateral solidification of a-Si thin films. Specifically, a dual xenon-arc-lamp-based system was utilized to induce location-controlled compl...
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In this paper we show that a flash lamp can be employed to induce controlled lateral solidification of a-Si thin films. Specifically, a dual xenon-arc-lamp-based system was utilized to induce location-controlled complete melting by shaping the incident beam using a contact mask. The resulting laterally solidified microstructure consisted of exceptionally long grains (~10s to ~100s of μm) that were relatively free of intragrain-defects. With further development and optimization, the approach may lead to cost-effective/high-throughput processes and systems that can capture and enhance the advantages of laser-based/melt-mediated crystallization techniques.
This paper generalizes the single-shell Kidder's self-similar solution to the double-shell one with a discontinuity in density across the interface. An isentropic implosion model is constructed to study the Rayleigh-...
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This paper generalizes the single-shell Kidder's self-similar solution to the double-shell one with a discontinuity in density across the interface. An isentropic implosion model is constructed to study the Rayleigh-Taylor instability for the implosion compression. A Godunov-type method in the Lagrangian coordinates is used to compute the one-dimensional Euler equation with the initial and boundary conditions for the double-shell Kidder's self-similar solution in spherical geometry. Numerical results are obtained to validate the double-shell implosion model. By programming and using the linear perturbation codes, a linear stability analysis on the Rayleigh-Taylor instability for the double-shell isentropic implosion model is performed. It is found that, when the initial perturbation is concentrated much closer to the interface of the two shells, or when the spherical wave number becomes much smaller, the modal radius of the interface grows much faster, i.e., more unstable. In addition, from the spatial point of view for the compressibility effect on the perturbation evolution, the compressibility of the outer shell has a destabilization effect on the Rayleigh-Taylor instability, while the compressibility of the inner shell has a stabilization effect.
Charge transfer due to collisions of ground-state N6+(1s2S) with atomic hydrogen has been investigated theoretically using the quantum-mechanical molecular-orbital close-coupling (QMOCC) method, in which the adiabatic...
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Charge transfer due to collisions of ground-state N6+(1s2S) with atomic hydrogen has been investigated theoretically using the quantum-mechanical molecular-orbital close-coupling (QMOCC) method, in which the adiabatic potentials and nonadiabatic couplings were obtained using the multireference single- and double-excitation configuration-interaction (MRDCI) approach. Total, n-, l-, and S-resolved cross sections have been obtained for energies between 10 meV/u and 10 keV/u. The QMOCC results were compared to available experimental and theoretical data as well as to merged-beams measurements and atomic-orbital close-coupling and classical trajectory Monte Carlo calculations. The accuracy of the QMOCC charge-transfer cross sections was found to be sensitive to the accuracy of the adiabatic potentials and couplings. Consequently, we developed a method to optimize the atomic basis sets used in the MRDCI calculations for highly charged ions. Since cross sections, especially those that are state selective, are necessary input for x-ray emission simulation of heliospheric and Martian exospheric spectra arising from solar wind ion–neutral gas collisions, a recommended set of state-selective cross sections, based on our evaluation of the calculations and measurements, is provided.
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