Article
Physics, Fluids & Plasmas
S. Diederichs, C. Benedetti, E. Esarey, M. Thevenet, J. Osterhoff, C. B. Schroeder
Summary: This study demonstrates the intrinsic stability of beam propagation in a plasma column, which is crucial in plasma-based positron acceleration schemes.
PHYSICS OF PLASMAS
(2022)
Article
Physics, Fluids & Plasmas
Lars Reichwein, Alexander Pukhov, Anton Golovanov, Igor Yu Kostyukov
Summary: This article proposes a setup for positron acceleration and studies its effectiveness through simulations. The results show that a twofold plasma column structure created by an electron driver and a laser pulse is capable of accelerating positron bunches over long distances.
Article
Physics, Fluids & Plasmas
Gianluca Sarri, Luke Calvin, Matthew Streeter
Summary: Plasma-based positron sources with broad energy tuneability and ultra-short duration are suitable for industrial, material science, and fundamental scientific applications.
PLASMA PHYSICS AND CONTROLLED FUSION
(2022)
Article
Physics, Fluids & Plasmas
Cheong R. Choi, M. -H. Woo, Kwangsun Ryu, D. -Y. Lee, P. H. Yoon
Summary: This paper presents a general wave dispersion relation for warm magnetized plasma, focusing on low frequency and slow phase speed. The results show three eigen modes, including fast, slow, and kinetic Alfven waves, as well as higher-frequency modes. It is found that the electric field along the ambient magnetic field is purely transverse for each mode.
PHYSICS OF PLASMAS
(2023)
Article
Physics, Fluids & Plasmas
Xin-Zhe Zhu, Min Chen, Bo-Yuan Li, Feng Liu, Xu-Lei Ge, Zheng-Ming Sheng, Jie Zhang
Summary: By using multi-stage plasma channels and relay acceleration, the energy and efficiency of laser wakefield accelerators can be significantly increased, addressing the issue of electron dephasing.
PHYSICS OF PLASMAS
(2022)
Article
Physics, Applied
Bo Peng, Chao Feng, Zhen Wang, Jianfei Hua, Yipeng Wu, Haixiao Deng, Fei Li, Wei Lu, Zhentang Zhao
Summary: A method is proposed to generate high-power XFEL radiation with tunable spectral bandwidth using plasma wakefield acceleration. The ultrabroad bandwidth is achieved by chirping the electron beam in a hollow-channel plasma without significant degradation of beam quality. Numerical simulations demonstrate the obtainment of a relative spectral bandwidth (full width) of up to 24% with optimized beam and plasma parameters.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Multidisciplinary
Zhangli Xu, Baifei Shen, Meiyu Si, Yongsheng Huang
Summary: We propose a scheme for positron acceleration using intense terahertz (THz) waves and a large-charge electron beam in a plasma channel. The THz wave evolves into a transversely uniform acceleration field and a weakly focusing/defocusing lateral field in the channel. The THz wave is generated through coherent transition radiation as the electron beam passes through a metal foil, as well as the wakefield in the plasma channel. The electron beam continuously supplies energy to the THz wave. This scheme allows for long-distance positron acceleration while maintaining beam quality, and simulations demonstrate the acceleration of positrons from 1 GeV to 126.8 GeV over a 1 m distance with a charge of approximately 10 pC and energy spread of 2.2%. The scheme can utilize electron beams from laser-driven or conventional accelerators, offering prospects for high-quality and flexible THz-driven relativistic positron sources of approximately 100 GeV.
NEW JOURNAL OF PHYSICS
(2023)
Article
Mechanics
Jorge Yanez, Fernando Veiga-Lopez
Summary: This paper presents a theoretical analysis of the condensation of combustion products in narrow gaps between planar plates, based on empirical results and lacking theoretical descriptions. The simplified formulation exclusively containing the gaseous phase allows for analytical expressions that qualitatively explain the effects of physical phenomena on the process. Despite its simplicity, the model predicts similar cycles of condensation-vaporization-condensation observed in laboratory experiments.
Article
Physics, Multidisciplinary
Qiang Chen, Dominika Maslarova, Junzhi Wang, Shao Xian Lee, Vojtech Horny, Donald Umstadter
Summary: This study presents the first experiment of transverse laser interference for electron injection into laser plasma accelerators. Simulation results show that this injection method, different from previous methods, traps electrons into later acceleration buckets. With optimal plasma tapering, the dephasing limit of these unprecedented electron beams could be potentially increased. The simulations and experiments confirm the acceleration of spatially dual electron beams induced by the interference.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Shiyu Zhou, Jianfei Hua, Weiming An, Warren B. Mori, Chan Joshi, Jie Gao, Wei Lu
Summary: This study presents a novel approach to achieve rapid high-energy acceleration of positrons through symmetric focusing methods in a hollow plasma channel, which can improve the energy extraction efficiency and reduce the energy spread of positrons. Further optimization is feasible for even better results.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Qianqian Jin, Shi Chen, Zhaoyou Chu, Benjin Chen, Wanni Wang, Juan Yang, Yongxin Jiang, Min Shao, Haisheng Qian
Summary: In this study, ZNSP hollow nanostructures with good biocompatibility were developed, which could effectively kill common bacteria and exhibit good biodegradability, making it suitable for potential antibacterial therapies.
MATERIALS CHEMISTRY FRONTIERS
(2022)
Article
Physics, Fluids & Plasmas
M. A. H. Zosa, M. Murakami
Summary: Microbubble implosion (MBI) is a novel mechanism with potential applications. This paper studies MBI under finite sphere conditions and calculates the optimal parameters for filling the hollow cavity.
PHYSICS OF PLASMAS
(2022)
Article
Multidisciplinary Sciences
Omri Seemann, Yang Wan, Sheroy Tata, Eyal Kroupp, Victor Malka
Summary: The high intensities reached by powerful lasers today allow us to explore the interaction with matter in the relativistic regime, pushing the frontiers of plasma physics. Refractive-plasma optics are being used in laser plasma accelerators, but their use for spatial phase control of the laser beam has not been successful due to manufacturing complications. However, this concept has now been successfully demonstrated, enabling phase manipulation near the focus position, where the intensity is already relativistic, and offering flexible control for high-intensity high-density interactions.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Applied
Dan M. Goebel, Giulia Becatti, Ioannis G. Mikellides, Alejandro Lopez Ortega
Summary: Hollow cathode plasma discharges are crucial for various applications, and recent progress in hollow cathode modeling and performance is important for technological advancements. Developments have been driven by electric propulsion demands, but apply to all thermionic hollow cathodes. Advances in 2D global simulations, hollow cathode plume instabilities, and cathode technologies are discussed, along with remaining challenges.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Astronomy & Astrophysics
Akash Bose, Subenoy Chakraborty
Summary: The paper deals with non-equilibrium thermodynamics associated with warm inflation and explores an assumption that is not realistic in practical analysis. It suggests that a variable cosmological constant may accommodate the quasi-stable process in warm inflation with a non-equilibrium thermodynamic description.
PHYSICS OF THE DARK UNIVERSE
(2022)
Article
Physics, Nuclear
M. Turner, P. Muggli, E. Adli, R. Agnello, M. Aladi, Y. Andrebe, O. Apsimon, R. Apsimon, A-M Bachmann, M. A. Baistrukov, F. Batsch, M. Bergamaschi, P. Blanchard, P. N. Burrows, B. Buttenschoen, A. Caldwell, J. Chappell, E. Chevallay, M. Chung, D. A. Cooke, H. Damerau, C. Davut, G. Demeter, L. H. Deubner, A. Dexter, G. P. Djotyan, S. Doebert, J. Farmer, A. Fasoli, V. N. Fedosseev, R. Fiorito, R. A. Fonseca, F. Friebel, I Furno, L. Garolfi, S. Gessner, B. Goddard, I Gorgisyan, A. A. Gorn, E. Granados, M. Granetzny, O. Grulke, E. Gschwendtner, V Hafych, A. Hartin, A. Helm, J. R. Henderson, A. Howling, M. Huether, R. Jacquier, S. Jolly, I. Yu Kargapolov, M. A. Kedves, F. Keeble, M. D. Kelisani, S-Y Kim, F. Kraus, M. Krupa, T. Lefevre, Y. Li, L. Liang, S. Liu, N. Lopes, K. Lotov, M. Martyanov, S. Mazzoni, D. Medina Godoy, V. A. Minakov, J. T. Moody, P. I. Morales Guzman, M. Moreira, H. Panuganti, A. Pardons, F. Pena Asmus, A. Perera, A. Petrenko, J. Pucek, A. Pukhov, B. Raczkevi, R. L. Ramjiawan, S. Rey, H. Ruhl, H. Saberi, O. Schmitz, E. Senes, P. Sherwood, L. O. Silva, P. Tuev, F. Velotti, L. Verra, V. A. Verzilov, J. Vieira, C. P. Welsch, B. Williamson, M. Wing, J. Wolfenden, B. Woolley, G. Xia, M. Zepp, G. Zevi Della Porta
PHYSICAL REVIEW ACCELERATORS AND BEAMS
(2020)
Article
Physics, Multidisciplinary
J. Vieira, M. Pardal, J. T. Mendonca, R. A. Fonseca
Summary: Superradiance is an anomalous radiance describing coherent photon emission from a gas, playing a crucial role in atomic physics, quantum mechanics, and astrophysics. The intensity of superradiant light beams is proportional to the number of particles squared, making it at the core of powerful light sources today. A new superradiance effect has been predicted to occur even when the particle number per wavelength approaches zero.
Article
Multidisciplinary Sciences
Rafal Zgadzaj, T. Silva, V. K. Khudyakov, A. Sosedkin, J. Allen, S. Gessner, Zhengyan Li, M. Litos, J. Vieira, K. V. Lotov, M. J. Hogan, V. Yakimenko, M. C. Downer
NATURE COMMUNICATIONS
(2020)
Article
Physics, Fluids & Plasmas
J. P. Palastro, B. Malaca, J. Vieira, D. Ramsey, T. T. Simpson, P. Franke, J. L. Shaw, D. H. Froula
Summary: By shaping laser pulses spatially and temporally, a novel regime of plasma wave excitation and wakefield acceleration has been introduced to achieve arbitrarily high electric fields while avoiding unwanted electron trapping.
PHYSICS OF PLASMAS
(2021)
Article
Physics, Fluids & Plasmas
U. Sinha, K. M. Schoeffler, J. Martins, J. Vieira, R. A. Fonseca, L. O. Silva
Summary: This study demonstrates that the Weibel or current filamentation instability can result in circularly polarized radiation, with the level of circular polarization increasing with the initial plasma magnetization and saturating at around 13% when the magnetization exceeds 0.05. Additionally, it is shown that this effect requires an ion-electron mass ratio greater than unity.
JOURNAL OF PLASMA PHYSICS
(2021)
Article
Physics, Fluids & Plasmas
J. -L. Vay, A. Huebl, A. Almgren, L. D. Amorim, J. Bell, L. Fedeli, L. Ge, K. Gott, D. P. Grote, M. Hogan, R. Jambunathan, R. Lehe, A. Myers, C. Ng, M. Rowan, O. Shapoval, M. Thevenet, H. Vincenti, E. Yang, N. Zaim, W. Zhang, Y. Zhao, E. Zoni
Summary: WarpX is a fully electromagnetic particle-in-cell code developed by the U.S. DOE Exascale Computing Project to model chains of plasma accelerator stages on exascale supercomputers. It utilizes the latest algorithmic advances and GPU architectures for simulations.
PHYSICS OF PLASMAS
(2021)
Correction
Physics, Multidisciplinary
J. Vieira, M. Pardal, J. T. Mendonca, R. A. Fonseca
Article
Computer Science, Theory & Methods
A. Myers, A. Almgren, L. D. Amorim, J. Bell, L. Fedeli, L. Ge, K. Gott, D. P. Grote, M. Hogan, A. Huebl, R. Jambunathan, R. Lehe, C. Ng, M. Rowan, O. Shapoval, M. Thevenet, J-L Vay, H. Vincenti, E. Yang, N. Zaim, W. Zhang, Y. Zhao, E. Zoni
Summary: WarpX is a general-purpose electromagnetic particle-in-cell code that was originally designed to run on multi-core CPU architectures. Through the strategy based on the AMReX library, it can now utilize GPU-accelerated nodes on OLCF's Summit supercomputer. The research summarizes the encountered challenges, lessons learned, and current performance results on relevant benchmark problems.
PARALLEL COMPUTING
(2021)
Article
Optics
Marco Piccardo, Michael de Oliveira, Veronica R. R. Policht, Mattia Russo, Benedetto Ardini, Matteo Corti, Gianluca Valentini, Jorge Vieira, Cristian Manzoni, Giulio Cerullo, Antonio Ambrosio
Summary: By introducing a diffractive axicon in a pulse shaper, topological-spectral correlation can be imparted to ultrafast pulses in the visible region with a large range of topological charges. This approach allows for the synthesis of ultrashort pulses with tailored spatial and temporal properties, enabling new possibilities in multimode photonics. The use of a diffractive axicon with circular geometry and a hyperspectral off-axis holography technique enables the control and manipulation of various properties of wave packets.
Article
Physics, Multidisciplinary
Camilla Willim, Jorge Vieira, Victor Malka, Luis O. Silva
Summary: An efficient approach utilizing a high-intensity twisted laser of moderate energy is proposed to generate collimated proton bunches with multi-10 MeV energies from a double-layer hydrogen target. Three-dimensional particle-in-cell simulations show the formation of a highly collimated and energetic proton bunch, with a divergence 6.5 times smaller compared to a Gaussian laser with the same energy. Theoretical modeling supports the consistent acceleration of high-energetic proton bunches with low divergence under experimentally feasible conditions for twisted drivers.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Physics, Multidisciplinary
Jacob R. Pierce, John P. Palastro, Fei Li, Bernardo Malaca, Dillon Ramsey, Jorge Vieira, Kathleen Weichman, Warren B. Mori
Summary: Spatiotemporal control refers to optical techniques that structure laser pulses with spacetime-dependent properties. The concept of arbitrarily structured laser (ASTRL) pulses is introduced, which generalizes these techniques. ASTRL pulses can be used for various laser-based applications, including laser wakefield acceleration, inertial confinement fusion, nanophotonics, and attosecond physics.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Physics, Fluids & Plasmas
T. Silva, B. Afeyan, L. O. Silva
Summary: The shape of the anisotropic velocity distribution function beyond Maxwellians can significantly influence the evolution of the Weibel instability and the dynamics of self-generated magnetic fields. Different laser-plasma interaction model distributions show that closer scrutiny may be needed for the Weibel generated magnetic fields beyond the second moment anisotropy ratio characterization.