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31.
In this article, the effect of ionization on the energy spectrum of electrons within the interaction of a laser pulse with hydrogen atoms is investigated using particle-in-cell simulation codes. The results show that the behaviour of electrons' energy distribution function in the field-ionized plasma, which occurred due to the field ionization, compared with that in the pre-plasma strongly depends on the pulse shape. For short rise-time pulses (here 30 fs), due to the rapid enhancement of laser electric field, ionization occurs quickly, and as a result, there is not much difference in the electron energy in both the media. However, for pulses with rise time of 40 fs, in the pre-plasma state, the electron population reaches higher energies compared with the field-ionized plasma state. The main reason for this difference is the nonlinear wave breaking that happens earlier due to density inhomogeneity in the field-ionized plasma. On the other hand, at longer rise-time pulses (here 60 and 70 fs), electrons achieve higher energies in the field-ionized plasma than those in the case of pre-plasma. In this case, because of density fluctuations in the field-ionized plasma, the Raman backscattered radiations are seeded by a strong initial noise at the earlier times and the Mendonca condition for chaos threshold is met sooner. Therefore, the electrons gain more energy through the stochastic mechanism that is in agreement with chaotic nature of the motion. 相似文献
32.
M. Amar D. Andreucci R. Gianni C. Timofte 《Journal of Mathematical Analysis and Applications》2021,493(2):124533
We prove a well-posedness result for two pseudo-parabolic problems, which can be seen as two models for the same electrical conduction phenomenon in heterogeneous media, neglecting the magnetic field. One of the problems is the concentration limit of the other one, when the thickness of the dielectric inclusions goes to zero. The concentrated problem involves a transmission condition through interfaces, which is mediated by a suitable Laplace-Beltrami type equation. 相似文献
33.
Kobayashi M. Zhang Y. Ishikawa H. Sun J. Oddershede J. Juul Jensen D. Miura H. 《Experimental Mechanics》2021,61(5):817-828
Experimental Mechanics - The internal strain distribution developing during plastic deformation is important for understanding the mechanical properties of polycrystalline materials. Such... 相似文献
34.
Lokoshchenko A. M. Fomin L. V. Basalov Yu. G. 《Journal of Applied Mechanics and Technical Physics》2021,62(6):981-990
Journal of Applied Mechanics and Technical Physics - This paper describes a problem of steady-state creep of a long narrow rectangular membrane in the case of a linear dependence between the... 相似文献
35.
Kazei Z. A. Snegirev V. V. Stolyarenko M. S. 《Journal of Experimental and Theoretical Physics》2021,133(5):591-598
Journal of Experimental and Theoretical Physics - The structural (lattice metric) and elastic characteristics of ErBaCo4O7 + x cobaltites, which are subjected to different heat treatment and are... 相似文献
36.
Journal of Applied Spectroscopy - With the COVID-19 outbreak, many challenges are posed before the scientific world to curb this pandemic. The diagnostic testing, treatment, and vaccine development... 相似文献
37.
Dzhun I. O. Babaitsev G. V. Kozin M. G. Romashkina I. L. Shanova E. I. Chechenin N. G. 《Physics of the Solid State》2021,63(6):825-831
Physics of the Solid State - The external factors which influence the ferromagnetic resonance (FMR) line width in bilayer (ferromagnet/antiferromagnet) exchange-biased systems are studied. The... 相似文献
38.
Mokshin A. V. Khusnutdinoff R. M. Vilf Ya. Z. Galimzyanov B. N. 《Theoretical and Mathematical Physics》2021,206(2):216-235
Theoretical and Mathematical Physics - In the framework of the concept of time correlation functions, we develop a self-consistent relaxation theory of the transverse collective particle dynamics... 相似文献
39.
Komarov Pavel D. Nifant’ev Ilya E. Roitershtein Dmitrii M. Minyaev Mikhail E. 《Journal of chemical crystallography》2021,51(3):352-362
Journal of Chemical Crystallography - The crystal structure of decakis(μ-chloro)-tetrakis(1,2,4-triphenylcyclopentadienyl)-hexakis(tetrahydrofuran)-di-potassium-tetra-neodymium(III)... 相似文献
40.
Theoretical and Mathematical Physics - We prove that for some initial data, solutions of the Cauchy problem for the nonlinear Schrödinger equation in the supercritical case are destroyed after... 相似文献