排序方式: 共有39条查询结果,搜索用时 187 毫秒
21.
H. Kotaki A. Yamazaki I. Daito M. Kando S. V. Bulanov T. Zh. Esirkepov S. Kondo S. Kanazawa T. Homma K. Nakajima Y. Oishi T. Nayuki T. Fujii K. Nemoto 《Laser Physics》2006,16(7):1107-1110
The results of experiments are presented for a single laser pulse interaction with a very low density gas target under conditions when the generated wake wave is below the wave-breaking threshold and the laser pulse power is lower than the critical power for relativistic self-focusing. A quasimonoenergetic electron beam is found to be stably generated for various laser pulse intensity values by controlling the acceleration length. 相似文献
22.
T. Utsumi K. Matsukado H. Daido T.Z. Esirkepov S.V. Bulanov 《Applied Physics A: Materials Science & Processing》2004,79(4-6):1185-1187
Melting and evaporation of matter due to pre-pulse irradiation of a high-peak-power ultra-short pulse laser onto a cold foil target and the expansion of laser-produced plasma are numerically evaluated using a hydrodynamic code based on CIP (cubic-interpolated propagation) and modified C-CUP (CIP-combined unified procedure) methods. The material properties of the solid, equation of state, laser absorption coefficient, skin depth, and thermal conductivity are consistently implemented. The formation and propagation of laser-produced plasmas are obtained with good numerical stability. PACS 02.70.-c; 52.38.Mf; 52.38.Kd 相似文献
23.
Energetic protons from a few-micron metallic foil evaporated by an intense laser pulse 总被引:1,自引:0,他引:1
Matsukado K Esirkepov T Kinoshita K Daido H Utsumi T Li Z Fukumi A Hayashi Y Orimo S Nishiuchi M Bulanov SV Tajima T Noda A Iwashita Y Shirai T Takeuchi T Nakamura S Yamazaki A Ikegami M Mihara T Morita A Uesaka M Yoshii K Watanabe T Hosokai T Zhidkov A Ogata A Wada Y Kubota T 《Physical review letters》2003,91(21):215001
With detailed experimental studies and hydrodynamics and particle-in-cell simulations we investigate the role of the prepulse in laser proton acceleration. The prepulse or pedestal (amplified spontaneous emission) can completely evaporate the irradiated region of a sufficiently thin foil; therefore, the main part of the laser pulse interacts with an underdense plasma. The multiparametric particle-in-cell simulations demonstrate that the main pulse generates the quasistatic magnetic field, which in its turn produces the long-lived charge separation electrostatic field, accelerating the ions. 相似文献
24.
T. Zh. Esirkepov Y. Sentoku K. Mima K. Nishihara F. Califano F. Pegoraro N. M. Naumova S. V. Bulanov Y. Ueshima T. V. Liseikina V. A. Vshivkov Y. Kato 《JETP Letters》1999,70(2):82-89
Ion acceleration by petawatt laser radiation in underdense and overdense plasmas is studied with 2D3V-PIC (Particle in Cell)
numerical simulations. These simulations show that the laser pulse drills a channel through the plasma slab, and electrons
and ions expand in vacuum. Fast electrons escape first from the electron-ion cloud. Later, ions gain a high energy on account
of the Coulomb explosion of the cloud and the inductive electric field which appears due to fast change of the magnetic field
generated by the laser pulse. Similarly, when a superintense laser pulse interacts with a thin slab of overdense plasma, its
ponderomotive pressure blows all the electrons away from a finite-diameter spot on the slab. Then, due to the Coulomb explosion,
ions gain an energy as high as 1 GeV.
Pis’ma Zh. éksp. Teor. Fiz. 70, No. 2, 80–86 (25 July 1999)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
25.
Pegoraro F. Bulanov S.V. Califano F. Esirkepov T.Z. Lisejkina T.V. Naumova N.M. Ruhl H. Vshivkov V.A. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2000,28(4):1177-1183
Acceleration of large populations of ions up to high (relativistic) energies may represent one of the most important and interesting tools that can be provided by the interaction of petawatt laser pulses with matter. In this paper, the basic mechanisms of ion acceleration by short laser pulses are studied in underdense plasmas. The ion acceleration does not originate directly from the pulse fields, but it is mediated by the electrons in the form of electrostatic fields originating from channeling, double layer formation and Coulomb explosion 相似文献
26.
A relativistic electromagnetic soliton solution in the model of a one-dimensional, unbounded, cold, collisionless plasma is
obtained without using the envelope approximation. The breaking of solitons with over-critical amplitudes is observed. The
stability of undercritical solitons and the breaking of overcritical solitons are demonstrated by a particle-in-cell computer
simulation.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 1, 33–38 (10 July 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
27.
S. V. Bulanov T. Zh. Esirkepov F. Califano Y. Kato T. V. Liseikina K. Mima N. M. Naumova K. Nishihara F. Pegoraro H. Ruhl Y. Sentoku Y. Ueshima 《JETP Letters》2000,71(10):407-411
A method is proposed for generating collimated beams of fast ions in laser-plasma interactions. Two-dimensional and three-dimensional particle-in-cell simulations show that the ponderomotive force expels electrons from the plasma region irradiated by a laser pulse. The ions with unneutralized electric charge that remain in this region are accelerated by Coulomb repulsive forces. The ions are focused by tailoring the target and also as a result of pinching in the magnetic field produced by the electric current of fast ions. 相似文献
28.
The electron, positron, and photon acceleration in the first cycle of a laser-driven wakefield is investigated. Separatrices between different types of the particle motion (trapped, reflected by the wakefield and ponderomotive potential, and transient) are demonstrated. The ponderomotive acceleration of electrons can be largely compensated by the wakefield action, in contrast to positrons and positively charged mesons. The electron bunch energy spectrum is analyzed. The maximum upshift of an electromagnetic wave frequency during reflection from the wakefield is obtained. 相似文献
29.
Laser ion-acceleration scaling laws seen in multiparametric particle-in-cell simulations 总被引:1,自引:0,他引:1
The ion acceleration driven by a laser pulse at intensity I= 10(20)-10(22) W/cm(2) x (microm/lambda)(2) from a double layer target is investigated with multiparametric particle-in-cell simulations. For targets with a wide range of thickness l and density n(e), at a given intensity, the highest ion energy gain occurs at certain electron areal density of the target sigma = n(e)l, which is proportional to the square root of intensity. In the case of thin targets and optimal laser pulse duration, the ion maximum energy scales as the square root of the laser pulse power. When the radiation pressure of the laser field becomes dominant, the ion maximum energy becomes proportional to the laser pulse energy. 相似文献
30.
Ultraintense laser pulses propagating in near-critical density plasmas generate magnetic dipole vortex structures. In the region of decreasing plasma density, the vortex expands both in forward and lateral directions. The magnetic field pressure pushes electrons and ions to form a density jump along the vortex axis and induces a longitudinal electric field. This structure moves together with the expanding dipole vortex. The background ions located ahead of the electric field are accelerated to high energies. The energy scaling of ions generated by this magnetic vortex acceleration mechanism is derived and corroborated using particle-in-cell simulations. 相似文献