In the present paper, we evaluated the core heating performance for FIREX-I class experiments by separating the heating process into 3 phases;1) energy coupling from heating laser to fast electrons η1, 2) fast electr...
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ISBN:
(纸本)9781622763313
In the present paper, we evaluated the core heating performance for FIREX-I class experiments by separating the heating process into 3 phases;1) energy coupling from heating laser to fast electrons η1, 2) fast electron core hitting rate η2 and 3) energy deposition rate in the core η3. Theobtained values and net coupling efficiencies ηnet for the cases w/o and with pre-plasma aresummarized in Table I. The existence of pre-plasma reduces the net coupling by 1/4. So reductionin pre-pulse level is indispensable for high heating efficiency. Another critical issue is the beamdivergence. In the present analysis, the field effects such as self-guiding by resistive B-field arenot included. When the beam divergence is as large as that obtained here, however, we cannotexpect the self-guiding effect on beam transport [4] So we should find the methodsfor reduction in the beam divergence and /or additional beam-collimation method to enhance the heating efficiency. Otherwise, the tip should be as close to core as possible. The further investigations (e.g., more practical FP simulations for transport process, and double cone effects) are going on.
With the increased availability of rich behavioral data sets, we present a novel combination of tools to analyze to analyze this information. Using criminal offense records as an example, we employ cross-correlation m...
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Nucleation of various ordered phases in block copolymers is studied by examining the free-energy landscape within the self-consistent field theory. The minimum energy path (MEP) connecting two ordered phases is comput...
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Nucleation of various ordered phases in block copolymers is studied by examining the free-energy landscape within the self-consistent field theory. The minimum energy path (MEP) connecting two ordered phases is computed using a recently developed string method. The shape, size, and free-energy barrier of critical nuclei are obtained from the MEP, providing information about the emergence of a stable ordered phase from a metastable phase. In particular, structural evolution of embryonic gyroid nucleus is predicted to follow two possible MEPs, revealing an interesting transition pathway with an intermediate perforated layered structure.
The emergence of low-cost sensing architectures for diverse modalities has made it possible to deploy sensor networks that acquire large amounts of very high-dimensional data. To cope with such a data deluge, manifold...
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We propose a nonlocal kinetic energy density functional (KEDF) for semiconductors based on the expected asymptotic behavior of its susceptibility function. The KEDF’s kernel depends on both the electron density and t...
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We propose a nonlocal kinetic energy density functional (KEDF) for semiconductors based on the expected asymptotic behavior of its susceptibility function. The KEDF’s kernel depends on both the electron density and the reduced density gradient, with an internal parameter formally related to the material’s static dielectric constant. We determine the accuracy of the KEDF within orbital-free density functional theory (DFT) by applying it to a variety of common semiconductors. With only two adjustable parameters, the KEDF reproduces quite well the exact noninteracting KEDF (i.e., Kohn-Sham DFT) predictions of bulk moduli, equilibrium volumes, and equilibrium energies. The two parameters in our KEDF are sensitive primarily to changes in the local crystal structure (such as atomic coordination number) and exhibit good transferability between different tetrahedrally-bonded phases. This local crystal structure dependence is rationalized by considering Thomas-Fermi dielectric screening theory.
We theoretically propose a method of producing single attosecond pulse by high-order harmonic generation with a two-color multicycle driver laser field. It is shown that this scheme can modulate the quantum paths by a...
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We theoretically propose a method of producing single attosecond pulse by high-order harmonic generation with a two-color multicycle driver laser field. It is shown that this scheme can modulate the quantum paths by adjusting the relative phase. In the case of the short quantum path control, a broadband supercontinuum spectrum with a 93 eV spectral width can be produced which directly generates an isolated 46 as pulse without phase compensation. When the long quantum path is picked out, a harmonic continuum spectrum with a bandwidth of 101 eV appears, an intense isolated 39 as pulse with high-signal-to-noise ratio is generated successfully by superposing some properly selected harmonics, the phases of which are locked. In both cases, our simulations show that the value of the time delay between two lasers can be varied between −0.2 fs and 0.2 fs to keep the isolated sub-50-as pulse generation. In particular, these results are analyzed by using both classical and three-dimensional quantum-mechanical approaches.
A controlled quantum system possesses a search landscape defined by the observable value as a functional of the control field. Within the search landscape, there exist level sets of controls giving the same observable...
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A controlled quantum system possesses a search landscape defined by the observable value as a functional of the control field. Within the search landscape, there exist level sets of controls giving the same observable value. This paper focuses on level sets of the transition probability P i¿f . For transition probabilities 0 < P i¿f < 1, a first order diffeomorphic modulation observable response preserving homotopy (D-MORPH) algorithm is utilized to investigate level sets. At the top of the control landscape, P i¿f = 1, a second order D-MORPH algorithm is presented that can explore the perfect control level set. D-MORPH is utilized to identify level set members that exhibit certain desirable secondary characteristics, e.g., minimal pulse fluence. Numerical simulations for finite level systems are presented to illustrate the variety of control behavior found across level set members.
The proton momentum distribution, accessible by deep inelastic neutron scattering, is a very sensitive probe of the potential of mean force experienced by the protons in hydrogen-bonded systems. In this work we introd...
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The proton momentum distribution, accessible by deep inelastic neutron scattering, is a very sensitive probe of the potential of mean force experienced by the protons in hydrogen-bonded systems. In this work we introduce a novel estimator for the end-to-end distribution of the Feynman paths, i.e., the Fourier transform of the momentum distribution. In this formulation, free particle and environmental contributions factorize. Moreover, the environmental contribution has a natural analogy to a free energy surface in statistical mechanics, facilitating the interpretation of experiments. The new formulation is not only conceptually but also computationally advantageous. We illustrate the method with applications to an empirical water model, ab initio ice, and one dimensional model systems.
In this paper, the interface width effects (i.e., the density gradient effects or the density transition layer effects) on the Rayleigh-Taylor instability (RTI) in the weakly nonlinear (WN) regime are investigated by ...
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Compositional lipid domains (lipid rafts) in plasma membranes are believed to be important components of many cellular processes. The mechanisms by which cells regulate the sizes, lifetimes, and spatial localization o...
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Compositional lipid domains (lipid rafts) in plasma membranes are believed to be important components of many cellular processes. The mechanisms by which cells regulate the sizes, lifetimes, and spatial localization of these domains are rather poorly understood at the moment. We propose a robust mechanism for the formation of finite-sized lipid raft domains in plasma membranes, the competition between phase separation in an immiscible lipid system and active cellular lipid transport processes naturally leads to the formation of such domains. Simulations of a continuum model reveal that the raft size distribution is broad and the average raft size is strongly dependent on the rates of cellular and interlayer lipid transport processes. We demonstrate that spatiotemporal variations in the recycling may enable the cell to localize larger raft aggregates at specific parts along the membrane. Moreover, we show that membrane compartmentalization may further facilitate spatial localization of the raft domains. Finally, we demonstrate that local interactions with immobile membrane proteins can spatially localize the rafts and lead to further clustering.
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