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Moldabekov ZA, Lokamani M, Vorberger J, Cangi A, Dornheim T. Assessing the accuracy of hybrid exchange-correlation functionals for the density response of warm dense electrons. J Chem Phys 2023; 158:094105. [PMID: 36889956 DOI: 10.1063/5.0135729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We assess the accuracy of common hybrid exchange-correlation (XC) functionals (PBE0, PBE0-1/3, HSE06, HSE03, and B3LYP) within the Kohn-Sham density functional theory for the harmonically perturbed electron gas at parameters relevant for the challenging conditions of the warm dense matter. Generated by laser-induced compression and heating in the laboratory, the warm dense matter is a state of matter that also occurs in white dwarfs and planetary interiors. We consider both weak and strong degrees of density inhomogeneity induced by the external field at various wavenumbers. We perform an error analysis by comparing with the exact quantum Monte Carlo results. In the case of a weak perturbation, we report the static linear density response function and the static XC kernel at a metallic density for both the degenerate ground-state limit and for partial degeneracy at the electronic Fermi temperature. Overall, we observe an improvement in the density response when the PBE0, PBE0-1/3, HSE06, and HSE03 functionals are used, compared with the previously reported results for the PBE, PBEsol, local-density approximation, and AM05 functionals; B3LYP, on the other hand, does not perform well for the considered system. Additionally, the PBE0, PBE0-1/3, HSE06, and HSE03 functionals are more accurate for the density response properties than SCAN in the regime of partial degeneracy.
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Affiliation(s)
- Zhandos A Moldabekov
- Center for Advanced Systems Understanding (CASUS), Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-02826 Görlitz, Germany
| | - Mani Lokamani
- Information Services and Computing, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-01328 Dresden, Germany
| | - Jan Vorberger
- Insitute of Radiation Physics, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-01328 Dresden, Germany
| | - Attila Cangi
- Center for Advanced Systems Understanding (CASUS), Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-02826 Görlitz, Germany
| | - Tobias Dornheim
- Center for Advanced Systems Understanding (CASUS), Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-02826 Görlitz, Germany
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Zeng J, Ye C, Liu P, Gao C, Li Y, Yuan J. The Strong Enhancement of Electron-Impact Ionization Processes in Dense Plasma by Transient Spatial Localization. Int J Mol Sci 2022; 23:ijms23116033. [PMID: 35682711 PMCID: PMC9181145 DOI: 10.3390/ijms23116033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/24/2022] [Accepted: 05/25/2022] [Indexed: 02/01/2023] Open
Abstract
Recent experiments have observed much higher electron–ion collisional ionization cross sections and rates in dense plasmas than predicted by the current standard atomic collision theory, including the plasma screening effect. We suggest that the use of (distorted) plane waves for incident and scattered electrons is not adequate to describe the dissipation that occurs during the ionization event. Random collisions with free electrons and ions in plasma cause electron matter waves to lose their phase, which results in the partial decoherence of incident and scattered electrons. Such a plasma-induced transient spatial localization of the continuum electron states significantly modifies the wave functions of continuum electrons, resulting in a strong enhancement of the electron–ion collisional ionization of ions in plasma compared to isolated ions. Here, we develop a theoretical formulation to calculate the differential and integral cross sections by incorporating the effects of plasma screening and transient spatial localization. The approach is then used to investigate the electron-impact ionization of ions in solid-density magnesium plasma, yielding results that are consistent with experiments. In dense plasma, the correlation of continuum electron energies is modified, and the integral cross sections and rates increase considerably. For the ionization of Mg9+e+1s22s2S→1s21S+2e, the ionization cross sections increase several-fold, and the rates increase by one order of magnitude. Our findings provide new insight into collisional ionization and three-body recombination and may aid investigations of the transport properties and nonequilibrium evolution of dense plasma.
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Affiliation(s)
- Jiaolong Zeng
- College of Science, Zhejiang University of Technology, Hangzhou 310023, China
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
- Correspondence: (J.Z.); (J.Y.)
| | - Chen Ye
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
| | - Pengfei Liu
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
| | - Cheng Gao
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
| | - Yongjun Li
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
| | - Jianmin Yuan
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha 410073, China; (C.Y.); (P.L.); (C.G.); (Y.L.)
- Graduate School of China Academy of Engineering Physics, Beijing 100193, China
- Correspondence: (J.Z.); (J.Y.)
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Moldabekov Z, Vorberger J, Dornheim T. Density Functional Theory Perspective on the Nonlinear Response of Correlated Electrons across Temperature Regimes. J Chem Theory Comput 2022; 18:2900-2912. [PMID: 35484932 PMCID: PMC9097288 DOI: 10.1021/acs.jctc.2c00012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We explore a new formalism to study the nonlinear electronic density response based on Kohn-Sham density functional theory (KS-DFT) at partially and strongly quantum degenerate regimes. It is demonstrated that the KS-DFT calculations are able to accurately reproduce the available path integral Monte Carlo simulation results at temperatures relevant for warm dense matter research. The existing analytical results for the quadratic and cubic response functions are rigorously tested. It is demonstrated that the analytical results for the quadratic response function closely agree with the KS-DFT data. Furthermore, the performed analysis reveals that currently available analytical formulas for the cubic response function are not able to describe simulation results, neither qualitatively nor quantitatively, at small wavenumbers q < 2qF, with qF being the Fermi wavenumber. The results show that KS-DFT can be used to describe warm dense matter that is strongly perturbed by an external field with remarkable accuracy. Furthermore, it is demonstrated that KS-DFT constitutes a valuable tool to guide the development of the nonlinear response theory of correlated quantum electrons from ambient to extreme conditions. This opens up new avenues to study nonlinear effects in a gamut of different contexts at conditions that cannot be accessed with previously used path integral Monte Carlo methods.
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Affiliation(s)
- Zhandos Moldabekov
- Center for Advanced Systems Understanding (CASUS), D-02826 Görlitz, Germany.,Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-01328 Dresden, Germany
| | - Jan Vorberger
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-01328 Dresden, Germany
| | - Tobias Dornheim
- Center for Advanced Systems Understanding (CASUS), D-02826 Görlitz, Germany.,Helmholtz-Zentrum Dresden-Rossendorf (HZDR), D-01328 Dresden, Germany
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4
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Zhang P, Jin Y, Zan X, Liu P, Li Y, Gao C, Hou Y, Zeng J, Yuan J. Enhancement of electron-impact ionization induced by warm dense environments. Phys Rev E 2021; 104:035204. [PMID: 34654195 DOI: 10.1103/physreve.104.035204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
Studies have shown significant discrepancies between the recent experiment [Berg et al., Phys. Rev. Lett. 120, 055002 (2018)PRLTAO10.1103/PhysRevLett.120.055002] and current theoretical calculations on the electron-impact ionization cross section of ions in warm dense magnesium. Here, we present a systematic study the effects of the ionic correlations and free-electron screening on the electron-impact ionization of ions in warm dense matter. The ionic correlation and the free-electron screening effects yield additional Hermitian terms to the calculation of the ionic central-force-field potential, which significantly change the electronic structure compared with that of the isolated ion. In calculating the electron-impact ionization, we describe the impact and ionized electrons using a damped-distorted wave function, which considers the momentum relaxation of free electrons due to collisions with other free electrons and ions. We reproduce the electron-impact ionization process for Mg^{7+} in the solid-density plasma and increase the ionization cross section by one order of magnitude compared with that of the isolated ion, which excellently agrees with the experimental result of Berg et al.
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Affiliation(s)
- Ping Zhang
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Yang Jin
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Xiaolei Zan
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Pengfei Liu
- College of Advanced Interdisciplinary Studies, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Yongjun Li
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Cheng Gao
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Yong Hou
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
| | - Jiaolong Zeng
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
- College of Science, Zhejiang University of Technology, Hangzhou Zhejiang 310023, People's Republic of China
| | - Jianmin Yuan
- Department of Physics, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha Hunan 410073, People's Republic of China
- Graduate School, China Academy of Engineering Physics, Beijing 100193, People's Republic of China
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Presura R, Wallace MS, Haque SH, Pohl I, Lake PW, Wu M. Extension of single-crystal x-ray spectropolarimetry with cubic crystals beyond perfect polarization-splitting geometries. Rev Sci Instrum 2021; 92:073102. [PMID: 34340451 DOI: 10.1063/5.0047035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 06/16/2021] [Indexed: 06/13/2023]
Abstract
The single-crystal spectropolarimeter envisioned by Baronova and Stepanenko splits an incident x-ray beam into two beams with mutually orthogonal linear polarizations by using simultaneous reflections at the perfectly polarizing 45° Bragg angle on certain pairs of internal planes in hexagonal or cubic crystals. These planes intersect along a threefold symmetry axis, making a 120° angle with each other, and are typically symmetric with respect to the crystal surface. In practice, the wavelength of the diagnostic x-ray lines does not exactly satisfy Bragg's law for the crystal in the ideal polarizing orientation, so the extinction of reflections is incomplete. Accepting this limitation, this paper shows that for cubic crystals, other pairs of internal planes exist that satisfy the polarization requirements approximately. Typically, they are accessible from the perfect polarization-splitting geometry by small rotations of the crystal. This paper includes examples of such planes for cubic crystals with {110} and {211} surface cuts.
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Affiliation(s)
- R Presura
- Nevada National Security Site, Sandia Operations, Albuquerque, New Mexico 87123, USA
| | - M S Wallace
- Nevada National Security Site, Livermore Operations, Livermore, California 94551, USA
| | - S H Haque
- Nevada National Security Site, Transformational Diagnostics and Imaging, Los Alamos, New Mexico 87544, USA
| | - I Pohl
- Nevada National Security Site, Sandia Operations, Albuquerque, New Mexico 87123, USA
| | - P W Lake
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - M Wu
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
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Lee JW, Kang G, Kim M, Kim M, Park SH, Kwon S, Yang S, Cho BI. Femtosecond soft X-ray absorption spectroscopy of warm dense matter at the PAL-XFEL. J Synchrotron Radiat 2020; 27:953-958. [PMID: 33566003 DOI: 10.1107/s160057752000524x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 04/14/2020] [Indexed: 06/12/2023]
Abstract
Free-electron laser pulse-based X-ray absorption spectroscopy measurements on warm dense copper are presented. The incident X-ray pulse energies were measured with a detector assembly consisting of a photocathode membrane and microchannel plates, and the transmitted energies were measured simultaneously with a photodiode detector. The precision of the absorption measurements was evaluated. For a warm dense copper foil irradiated by an intense femtosecond laser pulse, the enhanced X-ray absorption below the L3-edge, followed by the rapid evolution of highly excited Fermi liquid within a picosecond, were successfully measured. This result demonstrates a unique capability to study femtosecond non-equilibrium electron-hole dynamics in extreme states of matter.
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Affiliation(s)
- Jong Won Lee
- Department of Physics and Photon Science, GIST, Gwangju 61005, Republic of Korea
| | - Gyeongbo Kang
- Department of Physics and Photon Science, GIST, Gwangju 61005, Republic of Korea
| | - Minju Kim
- Department of Physics and Photon Science, GIST, Gwangju 61005, Republic of Korea
| | - Minseok Kim
- Pohang Accelerator Laboratory, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Sang Han Park
- Pohang Accelerator Laboratory, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Soonnam Kwon
- Pohang Accelerator Laboratory, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Seonghyeok Yang
- Department of Physics and Photon Science, GIST, Gwangju 61005, Republic of Korea
| | - Byoung Ick Cho
- Department of Physics and Photon Science, GIST, Gwangju 61005, Republic of Korea
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Braenzel J, Barriga-Carrasco MD, Morales R, Schnürer M. Charge-Transfer Processes in Warm Dense Matter: Selective Spectral Filtering for Laser-Accelerated Ion Beams. Phys Rev Lett 2018; 120:184801. [PMID: 29775363 DOI: 10.1103/physrevlett.120.184801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Indexed: 06/08/2023]
Abstract
We investigate, both experimentally and theoretically, how the spectral distribution of laser accelerated carbon ions can be filtered by charge exchange processes in a double foil target setup. Carbon ions at multiple charge states with an initially wide kinetic energy spectrum, from 0.1 to 18 MeV, were detected with a remarkably narrow spectral bandwidth after they had passed through an ultrathin and partially ionized foil. With our theoretical calculations, we demonstrate that this process is a consequence of the evolution of the carbon ion charge states in the second foil. We calculated the resulting spectral distribution separately for each ion species by solving the rate equations for electron loss and capture processes within a collisional radiative model. We determine how the efficiency of charge transfer processes can be manipulated by controlling the ionization degree of the transfer matter.
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Affiliation(s)
- J Braenzel
- Max Born Institute, Max Born Straße 2a, D-12489 Berlin, Germany
| | - M D Barriga-Carrasco
- E.T.S.I. Industriales, Universidad de Castilla-La Mancha, E-13071 Ciudad Real, Spain
| | - R Morales
- E.T.S.I. Industriales, Universidad de Castilla-La Mancha, E-13071 Ciudad Real, Spain
| | - M Schnürer
- Max Born Institute, Max Born Straße 2a, D-12489 Berlin, Germany
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Yuan C, Bogdanov EA, Kudryavtsev AA, Rabadanov KM, Zhou Z. Ambipolar field role in formation of electron distribution function in gas discharge plasma. Sci Rep 2017; 7:14613. [PMID: 29097805 DOI: 10.1038/s41598-017-15073-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 10/18/2017] [Indexed: 11/29/2022] Open
Abstract
It is shown that the local approximation for electron distribution function (EDF) determination at plasma periphery, where the ambipolar field is dominant, is not applicable even at high pressures when the characteristic plasma size exceeds the energy relaxation length of the electrons R > λε. Therefore, consistent results can be obtained only when solving the complete kinetic equation in both energy and spatial variables (i.e. it is necessary to solve nonlocal kinetic equation).
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Abstract
Continuum lowering is a well known and important physics concept that describes the ionization potential depression (IPD) in plasmas caused by thermal- or pressure-induced ionization of outer-shell electrons. The existing IPD models are often used to characterize plasma conditions and to gauge opacity calculations. Recent precision measurements have revealed deficits in our understanding of continuum lowering in dense hot plasmas. However, these investigations have so far been limited to IPD in strongly coupled but nondegenerate plasmas. Here, we report a first-principles study of the K-edge shifting in both strongly coupled and fully degenerate carbon plasmas, with quantum molecular dynamics calculations based on the all-electron density-functional theory. The resulting K-edge shifting versus plasma density, as a probe to the continuum lowering and the Fermi-surface rising, is found to be significantly different from predictions of existing IPD models. In contrast, a simple model of "single-atom-in-box," developed in this work, accurately predicts K-edge locations as ab initio calculations provide.
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Affiliation(s)
- S X Hu
- Laboratory for Laser Energetics, University of Rochester, 250 E. River Road, Rochester, New York 14623, USA
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Mo MZ, Shen X, Chen Z, Li RK, Dunning M, Sokolowski-Tinten K, Zheng Q, Weathersby SP, Reid AH, Coffee R, Makasyuk I, Edstrom S, McCormick D, Jobe K, Hast C, Glenzer SH, Wang X. Single-shot mega-electronvolt ultrafast electron diffraction for structure dynamic studies of warm dense matter. Rev Sci Instrum 2016; 87:11D810. [PMID: 27910490 DOI: 10.1063/1.4960070] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We have developed a single-shot mega-electronvolt ultrafast-electron-diffraction system to measure the structural dynamics of warm dense matter. The electron probe in this system is featured by a kinetic energy of 3.2 MeV and a total charge of 20 fC, with the FWHM pulse duration and spot size at sample of 350 fs and 120 μm respectively. We demonstrate its unique capability by visualizing the atomic structural changes of warm dense gold formed from a laser-excited 35-nm freestanding single-crystal gold foil. The temporal evolution of the Bragg peak intensity and of the liquid signal during solid-liquid phase transition are quantitatively determined. This experimental capability opens up an exciting opportunity to unravel the atomic dynamics of structural phase transitions in warm dense matter regime.
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Affiliation(s)
- M Z Mo
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - X Shen
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - Z Chen
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - R K Li
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - M Dunning
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - K Sokolowski-Tinten
- Faculty of Physics and Centre for Nanointegration Duisburg-Essen, University of Duisburg-Essen, Lotharstrasse 1, D-47048 Duisburg, Germany
| | - Q Zheng
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - S P Weathersby
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - A H Reid
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - R Coffee
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - I Makasyuk
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - S Edstrom
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - D McCormick
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - K Jobe
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - C Hast
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - S H Glenzer
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - X Wang
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
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Bang W, Albright BJ, Bradley PA, Vold EL, Boettger JC, Fernández JC. Linear dependence of surface expansion speed on initial plasma temperature in warm dense matter. Sci Rep 2016; 6:29441. [PMID: 27405664 PMCID: PMC4942619 DOI: 10.1038/srep29441] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 06/20/2016] [Indexed: 11/25/2022] Open
Abstract
Recent progress in laser-driven quasi-monoenergetic ion beams enabled the production of uniformly heated warm dense matter. Matter heated rapidly with this technique is under extreme temperatures and pressures, and promptly expands outward. While the expansion speed of an ideal plasma is known to have a square-root dependence on temperature, computer simulations presented here show a linear dependence of expansion speed on initial plasma temperature in the warm dense matter regime. The expansion of uniformly heated 1–100 eV solid density gold foils was modeled with the RAGE radiation-hydrodynamics code, and the average surface expansion speed was found to increase linearly with temperature. The origin of this linear dependence is explained by comparing predictions from the SESAME equation-of-state tables with those from the ideal gas equation-of-state. These simulations offer useful insight into the expansion of warm dense matter and motivate the application of optical shadowgraphy for temperature measurement.
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Affiliation(s)
- W Bang
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - B J Albright
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - P A Bradley
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - E L Vold
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - J C Boettger
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - J C Fernández
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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