Matter and Radiation at Extremes最新文献_第7页

Generating a tunable narrow electron beam comb via laser-driven plasma grating 通过激光驱动等离子体光栅产生可调谐窄电子束梳

1区物理与天体物理

Matter and Radiation at Extremes Pub Date : 2023-09-13 DOI: 10.1063/5.0151883

Hetian Yang, Jingwei Wang, Shixia Luan, Ke Feng, Wentao Wang, Ruxin Li

{"title":"Generating a tunable narrow electron beam comb via laser-driven plasma grating","authors":"Hetian Yang, Jingwei Wang, Shixia Luan, Ke Feng, Wentao Wang, Ruxin Li","doi":"10.1063/5.0151883","DOIUrl":"https://doi.org/10.1063/5.0151883","url":null,"abstract":"We propose a novel approach for generating a high-density, spatially periodic narrow electron beam comb (EBC) from a plasma grating induced by the interference of two intense laser pulses in subcritical-density plasma. We employ particle-in-cell (PIC) simulations to investigate the effects of cross-propagating laser pulses with specific angles overlapping in a subcritical plasma. This overlap results in the formation of a transverse standing wave, leading to a spatially periodic high-density modulation known as a plasma grating. The electron density peak within the grating can reach several times the background plasma density. The charge imbalance between electrons and ions in the electron density peaks causes mutual repulsion among the electrons, resulting in Coulomb expansion and acceleration of the electrons. As a result, some electrons expand into vacuum, forming a periodic narrow EBC with an individual beam width in the nanoscale range. To further explore the formation of the nanoscale EBC, we conduct additional PIC simulations to study the dependence on various laser parameters. Overall, our proposed method offers a promising and controlled approach to generate tunable narrow EBCs with high density.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135733680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electron acceleration in a coil target-driven low-β magnetic reconnection simulation 线圈靶驱动低β磁重联模拟中的电子加速

1区物理与天体物理

Matter and Radiation at Extremes Pub Date : 2023-09-13 DOI: 10.1063/5.0149259

Jiacheng Yu, Jiayong Zhong, Yongli Ping, Weiming An

{"title":"Electron acceleration in a coil target-driven low-<i>β</i> magnetic reconnection simulation","authors":"Jiacheng Yu, Jiayong Zhong, Yongli Ping, Weiming An","doi":"10.1063/5.0149259","DOIUrl":"https://doi.org/10.1063/5.0149259","url":null,"abstract":"Magnetic reconnection driven by a capacitor coil target is an innovative way to investigate low-β magnetic reconnection in the laboratory, where β is the ratio of particle thermal pressure to magnetic pressure. Low-β magnetic reconnection frequently occurs in the Earth’s magnetosphere, where the plasma is characterized by β ≲ 0.01. In this paper, we analyze electron acceleration during magnetic reconnection and its effects on the electron energy spectrum via particle-in-cell simulations informed by parameters obtained from experiments. We note that magnetic reconnection starts when the current sheet is down to about three electron inertial lengths. From a quantitative comparison of the different mechanisms underlying the electron acceleration in low-β reconnection driven by coil targets, we find that the electron acceleration is dominated by the betatron mechanism, whereas the parallel electric field plays a cooling role and Fermi acceleration is negligible. The accelerated electrons produce a hardened power-law spectrum with a high-energy bump. We find that injecting electrons into the current sheet is likely to be essential for further acceleration. In addition, we perform simulations for both a double-coil co-directional magnetic field and a single-coil one to eliminate the possibility of direct acceleration of electrons beyond thermal energies by the coil current. The squeeze between the two coil currents can only accelerate electrons inefficiently before reconnection. The simulation results provide insights to guide future experimental improvements in low-β magnetic reconnection driven by capacitor coil targets.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135734962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Direct imaging of shock wave splitting in diamond at Mbar pressure 毫巴压力下金刚石内部激波分裂的直接成像

1区物理与天体物理

Matter and Radiation at Extremes Pub Date : 2023-09-13 DOI: 10.1063/5.0156681

Sergey Makarov, Sergey Dyachkov, Tatiana Pikuz, Kento Katagiri, Hirotaka Nakamura, Vasily Zhakhovsky, Nail Inogamov, Victor Khokhlov, Artem Martynenko, Bruno Albertazzi, Gabriel Rigon, Paul Mabey, Nicholas J. Hartley, Yuichi Inubushi, Kohei Miyanishi, Keiichi Sueda, Tadashi Togashi, Makina Yabashi, Toshinori Yabuuchi, Takuo Okuchi, Ryosuke Kodama, Sergey Pikuz, Michel Koenig, Norimasa Ozaki

{"title":"Direct imaging of shock wave splitting in diamond at Mbar pressure","authors":"Sergey Makarov, Sergey Dyachkov, Tatiana Pikuz, Kento Katagiri, Hirotaka Nakamura, Vasily Zhakhovsky, Nail Inogamov, Victor Khokhlov, Artem Martynenko, Bruno Albertazzi, Gabriel Rigon, Paul Mabey, Nicholas J. Hartley, Yuichi Inubushi, Kohei Miyanishi, Keiichi Sueda, Tadashi Togashi, Makina Yabashi, Toshinori Yabuuchi, Takuo Okuchi, Ryosuke Kodama, Sergey Pikuz, Michel Koenig, Norimasa Ozaki","doi":"10.1063/5.0156681","DOIUrl":"https://doi.org/10.1063/5.0156681","url":null,"abstract":"Understanding the behavior of matter at extreme pressures of the order of a megabar (Mbar) is essential to gain insight into various physical phenomena at macroscales—the formation of planets, young stars, and the cores of super-Earths, and at microscales—damage to ceramic materials and high-pressure plastic transformation and phase transitions in solids. Under dynamic compression of solids up to Mbar pressures, even a solid with high strength exhibits plastic properties, causing the induced shock wave to split in two: an elastic precursor and a plastic shock wave. This phenomenon is described by theoretical models based on indirect measurements of material response. The advent of x-ray free-electron lasers (XFELs) has made it possible to use their ultrashort pulses for direct observations of the propagation of shock waves in solid materials by the method of phase-contrast radiography. However, there is still a lack of comprehensive data for verification of theoretical models of different solids. Here, we present the results of an experiment in which the evolution of the coupled elastic–plastic wave structure in diamond was directly observed and studied with submicrometer spatial resolution, using the unique capabilities of the x-ray free-electron laser (XFEL). The direct measurements allowed, for the first time, the fitting and validation of the 2D failure model for diamond in the range of several Mbar. Our experimental approach opens new possibilities for the direct verification and construction of equations of state of matter in the ultra-high-stress range, which are relevant to solving a variety of problems in high-energy-density physics.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135739846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Transition from backward to sideward stimulated Raman scattering with broadband lasers in plasmas 等离子体中宽带激光从向后到侧向受激拉曼散射的转变

1区物理与天体物理

Matter and Radiation at Extremes Pub Date : 2023-09-13 DOI: 10.1063/5.0152668

X. F. Li, S. M. Weng, P. Gibbon, H. H. Ma, S. H. Yew, Z. Liu, Y. Zhao, M. Chen, Z. M. Sheng, J. Zhang

{"title":"Transition from backward to sideward stimulated Raman scattering with broadband lasers in plasmas","authors":"X. F. Li, S. M. Weng, P. Gibbon, H. H. Ma, S. H. Yew, Z. Liu, Y. Zhao, M. Chen, Z. M. Sheng, J. Zhang","doi":"10.1063/5.0152668","DOIUrl":"https://doi.org/10.1063/5.0152668","url":null,"abstract":"Broadband lasers have been proposed as future drivers of inertial confined fusion (ICF) to enhance the laser–target coupling efficiency via the mitigation of various parametric instabilities. The physical mechanisms involved have been explored recently, but are not yet fully understood. Here, stimulated Raman scattering (SRS) as one of the key parametric instabilities is investigated theoretically and numerically for a broadband laser propagating in homogeneous plasma in multidimensional geometry. The linear SRS growth rate is derived as a function of scattering angles for two monochromatic laser beams with a fixed frequency difference δω. If δω/ω0 ∼ 1%, with ω0 the laser frequency, these two laser beams may be decoupled in stimulating backward SRS while remaining coupled for sideward SRS at the laser intensities typical for ICF. Consequently, side-scattering may dominate over backward SRS for two-color laser light. This finding of SRS transition from backward to sideward SRS is then generalized for a broadband laser with a few-percent bandwidth. Particle-in-cell simulations demonstrate that with increasing laser bandwidth, the sideward SRS gradually becomes dominant over the backward SRS. Since sideward SRS is very efficient in producing harmful hot electrons, attention needs to be paid on this effect if ultra-broadband lasers are considered as next-generation ICF drivers.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135733687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Simulations of spin/polarization-resolved laser–plasma interactions in the nonlinear QED regime 非线性QED中自旋/偏振分辨激光-等离子体相互作用的模拟

1区物理与天体物理

Matter and Radiation at Extremes Pub Date : 2023-09-13 DOI: 10.1063/5.0163929

Feng Wan, Chong Lv, Kun Xue, Zhen-Ke Dou, Qian Zhao, Mamutjan Ababekri, Wen-Qing Wei, Zhong-Peng Li, Yong-Tao Zhao, Jian-Xing Li

引用次数: 3

Characterization of hot electrons generated by laser–plasma interaction at shock ignition intensities 激波点火强度下激光等离子体相互作用产生的热电子的表征

1区物理与天体物理

Matter and Radiation at Extremes Pub Date : 2023-09-13 DOI: 10.1063/5.0157168

E. D. Filippov, M. Khan, A. Tentori, P. Gajdos, A. S. Martynenko, R. Dudzak, P. Koester, G. Zeraouli, D. Mancelli, F. Baffigi, L. A. Gizzi, S. A. Pikuz, Ph.D. Nicolaï, N. C. Woolsey, R. Fedosejevs, M. Krus, L. Juha, D. Batani, O. Renner, G. Cristoforetti

{"title":"Characterization of hot electrons generated by laser–plasma interaction at shock ignition intensities","authors":"E. D. Filippov, M. Khan, A. Tentori, P. Gajdos, A. S. Martynenko, R. Dudzak, P. Koester, G. Zeraouli, D. Mancelli, F. Baffigi, L. A. Gizzi, S. A. Pikuz, Ph.D. Nicolaï, N. C. Woolsey, R. Fedosejevs, M. Krus, L. Juha, D. Batani, O. Renner, G. Cristoforetti","doi":"10.1063/5.0157168","DOIUrl":"https://doi.org/10.1063/5.0157168","url":null,"abstract":"In an experiment carried out at the Prague Asterix Laser System at laser intensities relevant to shock ignition conditions (I &gt; 1016 W/cm2), the heating and transport of hot electrons were studied by using several complementary diagnostics, i.e., Kα time-resolved imaging, hard x-ray filtering (a bremsstrahlung cannon), and electron spectroscopy. Ablators with differing composition from low Z (parylene N) to high Z (nickel) were used in multilayer planar targets to produce plasmas with different coronal temperature and collisionality and modify the conditions of hot-electron generation. The variety of available diagnostics allowed full characterization of the population of hot electrons, retrieving their conversion efficiency, time generation and duration, temperature, and angular divergence. The obtained results are shown to be consistent with those from detailed simulations and similar inertial confinement fusion experiments. Based on the measured data, the advantages, reliability, and complementarity of the experimental diagnostics are discussed.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135734617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

A fresh class of superconducting and hard pentaborides 一类新的超导硬五硼化物

IF 5.1 1区物理与天体物理

Matter and Radiation at Extremes Pub Date : 2023-09-01 DOI: 10.1063/5.0157250

Hui Xie, Hong Wang, Fang Qin, Wei Han, Suxin Wang, Youchun Wang, F. Tian, D. Duan

{"title":"A fresh class of superconducting and hard pentaborides","authors":"Hui Xie, Hong Wang, Fang Qin, Wei Han, Suxin Wang, Youchun Wang, F. Tian, D. Duan","doi":"10.1063/5.0157250","DOIUrl":"https://doi.org/10.1063/5.0157250","url":null,"abstract":"On the basis of the current theoretical understanding of boron-based hard superconductors under ambient conditions, numerous studies have been conducted with the aim of developing superconducting materials with favorable mechanical properties using boron-rich compounds. In this paper, first-principles calculations reveal the existence of an unprecedented family of tetragonal pentaborides MB5 (M = Na, K, Rb, Ca, Sr, Ba, Sc, and Y), comprising B20 cages and centered metal atoms acting as stabilizers and electron donors to the boron sublattice. These compounds exhibit both superconductivity and high hardness, with the maximum superconducting transition temperature Tc of 18.6 K being achieved in RbB5 and the peak Vickers hardness Hv of 35.1 GPa being achieved in KB5 at 1 atm. The combination of these properties is particularly evident in KB5, RbB5, and BaB5, with Tc values of ∼14.7, 18.6, and 16.3 K and Hv values of ∼35.1, 32.4, and 33.8 GPa, respectively. The results presented here reveal that pentaborides can provide a framework for exploring and designing novel superconducting materials with favorable hardness at achievable pressures and even under ambient conditions.","PeriodicalId":54221,"journal":{"name":"Matter and Radiation at Extremes","volume":"8 1","pages":""},"PeriodicalIF":5.1,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82308141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Quantum splitting of electron peaks in ultra-strong fields 超强场中电子峰的量子分裂

IF 5.1 1区物理与天体物理

Matter and Radiation at Extremes Pub Date : 2023-09-01 DOI: 10.1063/5.0157663

Bo Zhang, Zhi-Meng Zhang, Wei-Min Zhou

引用次数: 0

Discovery of the Baijifeng impact structure in Tonghua, Jilin, China 吉林通化白芨峰冲击构造的发现

IF 5.1 1区物理与天体物理

Matter and Radiation at Extremes Pub Date : 2023-09-01 DOI: 10.1063/5.0172186

Ming Chen, Yang Lu, Jiahao Ning, Wenge Yang, J. Shu, Ho-Kwang Mao

引用次数: 0

Laser-driven electrodynamic implosion of fast ions in a thin shell 薄壳中快离子的激光驱动电动力学内爆