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Raman-Brillouin interplay for inertial confinement fusion relevant laser-plasma interaction

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High Power laser Science and Engineering 2016年第3期4卷 23-38页

作者： C.Riconda S.Weber LULI-UPMC UniversitParis 6:Sorbonne Universits CNRSEcole PolytechniqueCEA:Universit Paris-Saclay Institute of Physics of the ASCR

The co-existence of the Raman and Brillouin backscattering instability is an important issue for inertial confinement fusion. The present paper presents extensive one-dimensional(1D) particle-in-cell(PIC) simulations for a wide range of parameters extending and complementing previous findings. PIC simulations show that the scenario of reflectivity evolution and saturation is very sensitive to the temperatures, intensities, size of plasma and boundary conditions employed. The Langmuir decay instability is observed for rather small k_(epw)λ_D but has no influence on the saturation of Brillouin backscattering, although there is a clear correlation of Langmuir decay instability modes and ion-fractional decay for certain parameter ranges. Raman backscattering appears at any intensity and temperature but is only a transient phenomenon. In several configurations forward as well as backward Raman scattering is observed. For the intensities considered, I λ_o^2 above 10^(15) W μm^2/cm^2, Raman is always of bursty nature. A particular setup allows the simulation of multi-speckle aspects in which case it is found that Raman is self-limiting due to strong modifications of the distribution function. Kinetic effects are of prime importance for Raman backscattering at high temperatures. No unique scenario for the saturation of Raman scattering or Raman–Brillouin competition does exist. The main effect in the considered parameter range is pump depletion because of large Brillouin backscattering. However, in the low k_(epw)λ_D regime the presence of ion-acoustic waves due to the Langmuir decay instability from the Raman created electron plasma waves can seed the ion-fractional decay and affect the Brillouin saturation.

关键词： Brillouin backscattering inertial confinement fusion kinetic effects laser-plasma interaction parametric instabilities particle-in-cell simulations Raman backscattering

Modulational instability of the coupled waves between fast magnetosonic wave and slow Alfvén wave in the laser–plasma interaction

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plasma Science and Technology 2021年第1期23卷 15-22页

作者： Fangping WANG Juanfang HAN Wenshan DUAN College of Physics and Electronic Engineering Northwest Normal UniversityLanzhou 730070People’s Republic of China

By performing modulational instability analysis of the the nonlinear coupled dimensionless equations between a fast magnetosonic wave(FMSW)propagating obliquely with the magneticfield and a low-frequency slow Alfvén wave(SAW),we obtain the dispersion relation of the perturbation *** growth rate of the perturbation wave is *** is found that the growth rate increases as background magnetic field increases,which is in agreement with that reported by Tiwary et al(2016 *** 23122307).A critical perturbation wave number is *** the perturbation wave number is greater than or equal to the critical value,the growth rate is positive and it increases as the perturbation wave number increases,while the wave is *** maximum growth rate is reached when the frequency of the FMSW is half of the ion cyclotron *** minimum growth rate is reached when the propagation direction of the perturbation wave is the same as that of the FMSW.

关键词： modulational instability magnetic field amplification laser-plasma interaction

Detailed characterization of kHz-rate laser-driven fusion at a thin liquid sheet with a neutron detection suite

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High Power laser Science and Engineering 2024年第1期12卷 13-23页

作者： Benjamin M.Knight Connor M.Gautam Colton R.Stoner Bryan V.Egner Joseph R.Smith Chris M.Orban Juan J.Manfredi Kyle D.Frische Michael L.Dexter Enam A.Chowdhury Anil K.Patnaik Department of Engineering Physics Air Force Institute of TechnologyWPAFBOHUSA Physics Department Marietta CollegeMariettaOHUSA Department of Physics The Ohio State UniversityColumbusOHUSA Department of Materials Science and Engineering and Department of Electrical and Computer ScienceThe Ohio State UniversityColumbusOHUSA Intense Energy Solutions LLCPlain CityOHUSA

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mJ, 40 fs laser pulses on a thin(<1 μm) D_2O liquid sheet employing a measurement suite. At relativistic inte... 详细信息

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mJ, 40 fs laser pulses on a thin(laser±target interaction region. This high-repetition-rate laser-driven neutron source could provide a low-cost, on-demand test bed for radiation hardening and imaging applications.

关键词： high-repetition-rate laser-driven fusion laser-plasma interaction liquid target neutron detectors

Acceleration of 60 MeV proton beams in the commissioning experiment of the SULF-10 PW laser

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High Power laser Science and Engineering 2022年第4期10卷 36-44页

作者： A.X.Li C.Y.Qin H.Zhang S.Li L.L.Fan Q.S.Wang T.J.Xu N.W.Wang L.H.Yu Y.Xu Y.Q.Liu C.Wang X.L.Wang Z.X.Zhang X.Y.Liu P.L.Bai Z.B.Gan X.B.Zhang X.B.Wang C.Fan Y.J.Sun Y.H.Tang B.Yao X.Y.Liang Y.X.Leng B.F.Shen L.L.Ji R.X.Li Z.Z.Xu State Key Laboratory of High Field laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Shanghai Tech University Shanghai 201210China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBejing 100049China CAS Centerfor Excellence inUltra-intense laser Science Shanghai 201800China College of Science University of Shanghai for Science and TechnologyShanghai 200093China Department of Physics Shanghai Normal UniversityShanghai 200234China

We report the experimental results of the commissioning phase in the 10 PW laser beamline of the Shanghai Superintense Ultrafast laser Facility(SULF).The peak power reaches 2.4 PW on target without the last amplifying during the *** laser energy of 72±9 J is directed to a focal spot of approximately 6μm diameter(full width at half maximum)in 30 fs pulse duration,yielding a focused peak intensity around 2.0×10^(21)W/cm^(2).The first laser-proton acceleration experiment is performed using plain copper and plastic ***-energy proton beams with maximum cut-off energy up to 62.5 MeV are achieved using copper foils at the optimum target thickness of 4μm via target normal sheath *** plastic targets of tens of nanometers thick,the proton cut-off energy is approximately 20 MeV,showing ring-like or flamented density *** experimental results reflect the capabilities of the SULF-10 PW beamline,for example,both ultrahigh intensity and relatively good beam *** optimization for these key parameters is underway,where peak laser intensities of 10^(22)-10^(23)w/cm^(2)are anticipated to support various experiments on extreme field physics.

关键词： high-energy proton source laser-plasma interaction ultraintense lasers

Effects of substrate-ion density gradients on light-ion acceleration from ultraintense laser pulse irradiated thin-foils

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Chinese Physics B 2010年第7期19卷 369-376页

作者：刘明伟李儒新夏长权刘建胜徐至展 State Key Laboratory of High Field laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences

A general solution of the electrostatic potential that determines the maximum light-ion energy is derived for the test-particle acceleration model by taking into account the influence of the substrate-ion density gradient. It is shown that the substrate-ion density structure is also dependent on laser pulse duration. In the picosecond or sub-picosecond regime, the decreasing density gradient of the substrate-ions leads to an evident reduction in the acceleration efficiency of the light-ions. However, this kind of influence is negligible in the ultrashort regime.

关键词： laser-plasma interaction ion acceleration substrate-ion density gradient

Direct electron acceleration by chirped laser pulse in a cylindrical plasma channel

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Chinese Physics B 2020年第8期29卷 255-263页

作者： Yong-Nan Hu Li-Hong Cheng Zheng-Wei Yao Xiao-Bo Zhang Ai-Xia Zhang Ju-Kui Xue College of Physics and Electronics Engineering Northwest Normal UniversityLanzhou 730070China School of Science Guizhou University of Engineering ScienceBijie 551700China

We study the dynamics of single electron in an inhomogeneous cylindrical plasma channel during the direct acceleration by linearly polarized chirped laser *** adjusting the parameters of the chirped laser pulse and the plasma channel,we obtain the energy gain,trajectory,dephasing rate and unstable threshold of electron oscillation in the *** influences of the chirped factor and inhomogeneous plasma density distribution on the electron dynamics are discussed in *** find that the nonlinearly chirped laser pulse and the inhomogeneous plasma channel have strong coupled influence on the electron *** electron energy gain can be enhanced,the instability threshold of the electron oscillation can be lowered,and the acceleration length can be shortened by chirped laser,while the inhomogeneity of the plasma channel can reduce the amplitude of the chirped laser.

关键词： chirped laser pulse plasma channel laser-plasma interaction electron acceleration

Wakefield generation by chirped super-Gaussian laser pulse in inhomogeneous plasma

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plasma Science and Technology 2018年第11期20卷 28-36页

作者： Zhengwei YAO Lihong CHENG Rongan TANG Jukui XUE College of Physics and Electronics Engineering Northwest Normal UniversityLanzhou 730070People＇s Republic of China

We study the effect of nonlinearly chirped super-Gaussian （SG） laser pulse on wakefield generation in an inhomogeneous plasma. The different types of nonlinearly chirped pulse are employed, and different kinds of inhomogeneous plasma density are used. The maximum wakefield amplitude as the function of nonlinearly chirped laser pulse and inhomogeneous plasma density in parameter space are obtained. Moreover, the dependence of the maximum wakefield amplitude on the SG laser pulse index is discussed. This shows that a larger wakefield can be obtained when the chirped pulse and inhomogeneous density are in the critical regions. Wakefield generation can be controlled by adjusting the chirped SG pulse and inhomogeneous plasma density parameters. That is, we provide an efficient way for the controlled generation of the wakefield.

关键词： laser-plasma interaction inhomogeneous plasma plasma wakefield

Dense pair plasma generation and its modulation dynamics in counter-propagating laser field

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Chinese Physics B 2018年第10期27卷 433-439页

作者： Wei-Yuan Liu Wen Luo Tao Yuan Ji-Ye Yu Min Chen School of Nuclear Science and Technology University of South ChinaHengyang 421001China Key Laboratory for laser plasmas（MoE） School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China IFSA Collaborative Innovation Center Shanghai Jiao Tong UniversityShanghai 200240China

With two-dimensional quantum electrodynamics（QED） particle-in-cell simulations, a dense electron-positron（e^-e~＋） pair generation from laser-solid interactions is demonstrated. When the interaction of two linearly polarized laser pulses with a thin target enters into the relativistic transparency regime, a stable standing wave（SW） field can be formed by the overlap of the two counter-propagating laser pulses directly. The present study aims to clarify the effects of the S W field on the dynamics of e^-e^＋ pair plasmas. Our results indicate that under the combined effect of the SW field and radiation reaction（RR） effect, the created e^-e^＋ pairs can be trapped into the electric field nodes when the field strength is *** trapping effect contributes to the generation of γAV≥400 and ultra-dense pair plasmas in the two-side irradiation scheme. Despite different laser intensities, these pair plasmas have a Maxwellian spectral distribution with a peak energy of 150 MeV. Besides, the periodical modulation of the average energy, spatial, phase-space, and angular patterns of the e^-e^＋ pair plasmas can be triggered. In the angular patterns, as long as the SW field exists, pair plasmas can be pinched along the laser polarization direction. These results may offer a better understanding of the laser-solid interactions in the experiments when 10-PW laser facilities come into operation in the future.

关键词： PIC simulation laser-plasma interaction standing wave radiation reaction

Supersonic gas jet stabilization in laser–plasma acceleration

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High Power laser Science and Engineering 2023年第6期11卷 256-263页

作者： Zhen-Zhe Lei Yan-Jun Gu Zhan Jin Shingo Sato Alexei Zhidkov Alexandre Rondepierre Kai Huang Nobuhiko Nakanii Izuru Daito Masakai Kando Tomonao Hosokai SANKEN(Institute of Scientific and Industrial Research) Osaka UniversityIbarakiOsakaJapan Kansai Institute for Photon Science(KPSI) National Institutes for Quantum Science and Technology(QST)Kizugawa-cityKyotoJapan RIKEN SPring-8 Center SayoHyogoJapan

Supersonic gas jets generated via a conical nozzle are widely applied in the laser wakefield acceleration of *** stability of the gas jet is critical to the electron injection and the reproducibility of the wakefield *** we discussed the role of the stilling chamber in a modified converging-diverging nozzle to dissipate the turbulence and to stabilize the gas *** the fluid dynamics simulations and the Mach-Zehnder interferometer measurements,the instability originating from the nonlinear turbulence is studied and the mechanism to suppress the instability is *** the numerical and experimental results prove that the carefully designed nozzle with a stilling chamber is able to reduce the perturbation by more than 10% compared with a simple-conical nozzle.

关键词： shock injection hydrodynamic stability laser wakefield acceleration laser-plasma interaction