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Electron and ion acceleration from femtosecond laser-plasma peeler scheme

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arXiv 2022年

作者： Shen, X.F. Pukhov, A. Qiao, B. Institut für Theoretische Physik i Heinrich-Heine-Universität Düsseldorf Düsseldorf40225 Germany Center for Applied Physics and Technology Hedps Sklnp School of Physics Peking University Beijing100871 China

Using three-dimensional particle-in-cell simulations, we further investigate the electron and ion acceleration from femtosecond laser-plasma peeler scheme which was proposed in our recent paper (Shen et al 2021 Phys. Rev. X 11 041002). In addition to the standard setup where a laser pulse impinges on an edge of a single tape target, two new variants of the target, i.e., a parallel tape and a cross tape target, were proposed, where strong surface plasma waves can also be efficiently excited at the front edges of the target. By using a tabletop 200 TW-class laser pulse, we observe generation of high-flux, well-collimated, superponderomotive electrons. More importantly, quasimonoenergetic proton beams can always be obtained in all the three setups, while with the single tape case, the obtained proton beam has the highest peak energy and narrowest spectrum. Copyright © 2022, The Authors. All rights reserved.

关键词： Proton beams

Super-exponential behaviors of out-of-time ordered correlators and Loschmidt echo in a non-Hermitian interacting system

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arXiv 2023年

作者： Zhao, Wen-Lei Han, Chao Ke, Han Liu, Jie School of Science Jiangxi University of Science and Technology Ganzhou341000 China Key Laboratory of Low Dimensional Quantum Materials and Sensor Devices of Jiangxi Education Institutes Ganzhou341000 China Graduate School China Academy of Engineering Physics Beijing100193 China HEDPS Center for Applied Physics and Technology College of Engineering Peking University Beijing100871 China

We investigate the out-of-time ordered correlators and Loschmidt echo in a non-Hermitian interacting system governed by a Gross-Pitaevskii map model, which incorporates a periodically modulated complex strength of the nonlinear interaction as delta kicks. We uncover that the time evolutions of the out-of-time ordered correlators follow that of the Loschmidt echo in certain situations. In particular, we find that both of them can exhibit a super-exponential growth with time, indicating the emergence of super-exponential scrambling and instability. Interestingly, after a proper scaling scheme, we find that all the super-exponential behaviors approximately collapse on a scaling-law curve that is independent on the non-Hermitian parameter as well as the effective Planck constant. The underlying mechanism is rooted in the super-exponentially fast diffusion of energy as well as the norm of quantum states. Our findings suggest a kind of fastest divergence of two nearby quantum states, which has implication in information scrambling. © 2023, CC BY.

关键词： Quantum theory

Plasma kinetics: Discrete Boltzmann modeling and Richtmyer-Meshkov instability

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arXiv 2023年

作者： Song, Jiahui Xu, Aiguo Miao, Long Chen, Feng Liu, Zhipeng Wang, Lifeng Wang, Ningfei Hou, Xiao School of Aerospace Engineering Beijing Institute of Technology Beijing100081 China National Key Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing100088 China National Key Laboratory of Shock Wave and Detonation Physics Mianyang621900 China HEDPS Center for Applied Physics and Technology College of Engineering Peking University Beijing100871 China State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing100081 China Chongqing Innovation Center Beijing Institute of Technology Chongqing404100 China School of Aeronautics Shandong Jiaotong University Jinan250357 China Department of Physics School of Science Tianjin Chengjian University Tianjin300384 China

In this paper, a discrete Boltzmann model (DBM) for plasma kinetics is proposed and further used to investigate the non-equilibrium characteristics in Orszag-Tang (OT) vortex and Richtmyer-Meshkov instability (RMI) problems. The construction of DBM mainly considers two aspects. The first is to build a physical model with sufficient capability to capture underlying physics. The second is to devise schemes for extracting more valuable information from massive data. For the first aspect, the generated model is equivalent to a magnetohydrodynamic model, and a coarse-grained model for extracting the most relevant thermodynamic non-equilibrium (TNE) behaviors including the entropy production rate. For the second aspect, the DBM uses non-conserved kinetic moments of (f − feq) to describe the nonequilibrium states and behaviors of complex systems. It is found that: (i) For OT vortex, the entropy production rate and compression difficulty first increase then decrease with time. (ii) For RMI with interface inversion and re-shock process, the influence of magnetic field on TNE effects shows stages: before the interface inversion, the TNE strength is enhanced by delaying the interface inversion;while after the interface inversion, the TNE strength is significantly reduced. Both the global average TNE strength and entropy production rate contributed by non-organized energy flux can be used as physical criteria to identify whether or not the magnetic field is sufficient to prevent the interface inversion. In general, this paper proposes a generalized physical modeling scheme that has the potential for investigating the kinetic physics in plasma. © 2023, CC BY-NC-ND.

关键词： Vortex flow

Comparison study on atomic and molecular ellipticity dependence of high-order harmonic generation

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Physical Review A 2021年第4期103卷 043115-043115页

作者： Qinghua Gao Shi Chen Hongjing Liang Yichen Wang Chengrui Bi Shuai Ben Ri Ma Dajun Ding Jing Chen Institute of Atomic and Molecular Physics Jilin University Changchun 130012 China Center for Applied Physics and Technology HEDPS and School of Physics Peking University Beijing 100871 China Institute of Applied Physics and Computational Mathematics P.O. Box 8009 Beijing 100088 China Center for Advanced Material Diagnostic Technology College of Engineering Physics Shenzhen Technology University Shenzhen 518118 China

We systematically investigate ellipticity dependence of high-order harmonic generation of Ar and N2 in intense elliptically polarized laser fields. The experimental normalized ratios of low-order harmonic intensity to high-order harmonic intensity increase with ellipticity for both Ar and N2, and quantitatively depend on targets and trajectory paths. The experimental results are well reproduced by a nonadiabatic semiclassical simulation and explained by trajectory-based analysis. In addition, the influence of nuclear distance on the ratios is theoretically investigated. Our work reveals that the difference between atoms and molecules can be attributed to the influence of different ionic potentials, which depends on the molecular structure (internuclear distance) and alignment, on the evolution of the photoelectron.

关键词： High-order harmonic generation Atoms Molecules High-harmonic generation Semiclassical methods Ultrafast pump-probe spectroscopy

Stiffened gas approximation and GRP resolution for fluid flows of real materials

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arXiv 2021年

作者： Wang, Yue Li, Jiequan Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing100088 China HEDPS Center for Applied Physics and Technology College of Engineering Peking University Beijing100871 China

The equation of state (EOS) embodies thermodynamic properties of compressible fluid materials and usually has very complicated forms in real engineering applications, subject to the physical requirements of thermodynamics. The complexity of EOS in form gives rise to the difficulty in analyzing relevant wave patterns. Concerning the design of numerical algorithms, the complex EOS causes the inefficiency of Riemann solvers and even the loss of robustness, which hampers the development of Godunov-type numerical schemes. In this paper, a strategy of local stiffened gas approximation is proposed for real materials. The stiffened gas EOS is used to approximate general EOS locally at each interface of computational control volumes so that the Riemann solver can be significantly simplified. In the meantime, the generalized Riemann problem (GRP) solver is adopted not only for high resolution purpose but effective reflection of the local thermodynamics as well. The resulting scheme is demonstrated to be efficient and robust and numerical examples display the excellent performance of such an approximation. Copyright © 2021, The Authors. All rights reserved.

关键词： Thermodynamic properties

Growth rate and gain of stimulated Brillouin scattering considering nonlinear Landau damping due to particle trapping

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Growth rate and gain of stimulated Brillouin scattering cons...

作者： Feng, Q.S. Cao, L.H. Liu, Z.J. Hao, L. Zheng, C.Y. Ning, C. He, X.T. Institute of Applied Physics and Computational Mathematics Beijing100094 China Hedps Center for Applied Physics and Technology Peking University Beijing100871 China Shanghai Jiao Tong University Shanghai200240 China

Growth rate and gain of stimulated Brillouin scattering (SBS) considering the reduced Landau damping due to particle trapping has been proposed to predict the growth and average level of SBS reflectivity. Due to particle trapping, the reduced Landau damping has been taken used of to calculate the gain of SBS, which will make the simulation data of SBS average reflectivity be consistent to the Tang model better. Other nonlinear effects such as harmonic generation and pump depletion have been also considered in the later evolution of SBS. This work may solve the pending questions in laser-plasma interaction and have wide applications in parametric instabilities. © 2020 IOP Publishing Ltd.

关键词： Stimulated Brillouin scattering

Universality of the Dynamic Characteristic Relationship of Electron Correlation in the Two-Photon Double Ionization Process of a Helium-Like System

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Chinese physics Letters 2020年第11期37卷 27-32页

作者： Fei Li Yu-Jun Yang Jing Chen Xiao-Jun Liu Zhi-Yi Wei Bing-Bing Wang Laboratory of Optical Physics Beijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijing 100190China Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China Institute of Applied Physics and Computational Mathematics Beijing 100088China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100084China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

Universality of the dynamic characteristic relationship between the characteristic time tc and the two-electron Coulomb interaction energy V12 of the ground state in the two-photon double ionization process is investigated via changing the parameters of the two-electron atomic system and the corresponding laser *** numerical results show that the product tcV12 keeps constant around 4.1 in the cases of changing the nucleus charge,the electron charge,the electron mass,and changing simultaneously the nucleus charge and the electron *** results demonstrate that the dynamic characteristic relationship in the two-photon double ionization process is *** work sheds more light on the dynamic characteristic relationship in ultrafast processes and may find its application in measurements of attosecond pulses.

关键词： conditions. charge characteristic

High-order accurate well-balanced energy stable adaptive moving mesh finite difference schemes for the shallow water equations with non-flat bottom topography

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arXiv 2023年

作者： Zhang, Zhihao Duan, Junming Tang, Huazhong Center for Applied Physics and Technology HEDPS LMAM School of Mathematical Sciences Peking University Beijing100871 China Computational Mathematics and Simulation Science École Polytechnique Fédérale de Lausanne Lausanne1015 Switzerland Nanchang Hangkong University Jiangxi Province Nanchang330000 China

This paper proposes high-order accurate well-balanced (WB) energy stable (ES) adaptive moving mesh finite difference schemes for the shallow water equations (SWEs) with non-flat bottom topography. To enable the construction of the ES schemes on moving meshes, a reformulation of the SWEs is introduced, with the bottom topography as an additional conservative variable that evolves in time. The corresponding energy inequality is derived based on a modified energy function, then the reformulated SWEs and energy inequality are transformed into curvilinear coordinates. A two-point energy conservative (EC) flux is constructed, and high-order EC schemes based on such a flux are proved to be WB that they preserve the lake at rest. Then high-order ES schemes are derived by adding suitable dissipation terms to the EC schemes, which are newly designed to maintain the WB and ES properties simultaneously. The adaptive moving mesh strategy is performed by iteratively solving the Euler-Lagrangian equations of a mesh adaptation functional. The fully-discrete schemes are obtained by using the explicit strong-stability preserving third-order Runge-Kutta method. Several numerical tests are conducted to validate the accuracy, WB and ES properties, shock-capturing ability, and high efficiency of the schemes. Copyright © 2023, The Authors. All rights reserved.

关键词： Runge Kutta methods

Control of photoelectron interference dynamics with two-color laser fields

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Physical Review Research 2022年第1期4卷 013140-013140页

作者： Facheng Jin Weifeng Yang Xiwang Liu Hongdan Zhang Wenhui Dong Xiaohong Song Jing Chen Research Center for Advanced Optics and Photoelectronics Department of Physics College of Science Shantou University Shantou Guangdong 515063 China Faculty of Science Xi'an Aeronautical Institute Xi'an 710077 China Department of Physics School of Science Hainan University Haikou 570288 China Institute of Applied Physics and Computational Mathematics P.O. Box 8009 Beijing 100088 China HEDPS Center for Applied Physics and Technology Peking University Beijing 100084 China

We study the multiple interference structures in photoelectron momentum distributions (PMDs) of xenon atoms, whose dynamics can be manipulated effectively by a fundamental and weaker third-harmonic two-color laser fields, especially for an oblique interference pattern. It is found that this structure is only attributed to the contributions from the forward-scattered electrons as a Coulomb effect in strong-field physics. Further, the gross structure of the oblique interference arises from the forward-scattered electron ionized within a quarter-cycle of the fundamental field, and the fine structure is identified to originate from the intercycle interference of the trajectories. Moreover, we demonstrate that the multiple interference structure can be enhanced or suppressed by adjusting the relative phase of two colors. Our investigation shows that the two-color laser fields can be tailored with the purpose of manipulating specific dynamics process, which will be helpful to resolve ultrafast spatio-temporal information from the complex interference in strong-field ionization.

关键词： Atomic & molecular processes in external fields Multiphoton or tunneling ionization & excitation