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Wu HC, Meyer-Ter-Vehn J, Ruhl H, Sheng ZM. Terahertz radiation from a laser plasma filament. Phys Rev E Stat Nonlin Soft Matter Phys 2011; 83:036407. [PMID: 21517604 DOI: 10.1103/physreve.83.036407] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 01/16/2011] [Indexed: 05/30/2023]
Abstract
By the use of two-dimensional particle-in-cell simulations, we clarify the terahertz (THz) radiation mechanism from a plasma filament formed by an intense femtosecond laser pulse. The nonuniform plasma density of the filament leads to a net radiating current for THz radiation. This current is mainly located within the pulse and the first cycle of the wakefield. As the laser pulse propagates, a single-cycle and radially polarized THz pulse is constructively built up forward. The single-cycle shape is mainly due to radiation damping effect.
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Affiliation(s)
- H-C Wu
- Max-Planck-Institut für Quantenoptik, D-85748 Garching, Germany.
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2
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Yan XQ, Wu HC, Sheng ZM, Chen JE, Meyer-Ter-Vehn J. Self-organizing GeV, nanocoulomb, collimated proton beam from laser foil interaction at 7 x 10;{21} W/cm;{2}. Phys Rev Lett 2009; 103:135001. [PMID: 19905516 DOI: 10.1103/physrevlett.103.135001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Indexed: 05/28/2023]
Abstract
We report on a self-organizing, quasistable regime of laser proton acceleration, producing 1 GeV nanocoulomb proton bunches from laser foil interaction at an intensity of 7 x 10;{21} W/cm;{2}. The results are obtained from 2D particle-in-cell simulations, using a circular polarized laser pulse with Gaussian transverse profile, normally incident on a planar, 500 nm thick hydrogen foil. While foil plasma driven in the wings of the driving pulse is dispersed, a stable central clump with 1-2lambda diameter is forming on the axis. The stabilization is related to laser light having passed the transparent parts of the foil in the wing region and enfolding the central clump that is still opaque. Varying laser parameters, it is shown that the results are stable within certain margins and can be obtained both for protons and heavier ions such as He;{2+}.
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Affiliation(s)
- X Q Yan
- Max-Planck-Institut fuer Quantenoptik, D-85748 Garching, Germany.
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Schmid K, Veisz L, Tavella F, Benavides S, Tautz R, Herrmann D, Buck A, Hidding B, Marcinkevicius A, Schramm U, Geissler M, Meyer-Ter-Vehn J, Habs D, Krausz F. Few-cycle laser-driven electron acceleration. Phys Rev Lett 2009; 102:124801. [PMID: 19392288 DOI: 10.1103/physrevlett.102.124801] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2008] [Indexed: 05/27/2023]
Abstract
We report on an electron accelerator based on few-cycle (8 fs full width at half maximum) laser pulses, with only 40 mJ energy per pulse, which constitutes a previously unexplored parameter range in laser-driven electron acceleration. The produced electron spectra are monoenergetic in the tens-of-MeV range and virtually free of low-energy electrons with thermal spectrum. The electron beam has a typical divergence of 5-10 mrad. The accelerator is routinely operated at 10 Hz and constitutes a promising source for several applications. Scalability of the few-cycle driver in repetition rate and energy implies that the present work also represents a step towards user friendly laser-based accelerators.
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Affiliation(s)
- K Schmid
- Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching, Germany.
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Chalupský J, Juha L, Kuba J, Cihelka J, Hájková V, Koptyaev S, Krása J, Velyhan A, Bergh M, Caleman C, Hajdu J, Bionta RM, Chapman H, Hau-Riege SP, London RA, Jurek M, Krzywinski J, Nietubyc R, Pelka JB, Sobierajski R, Meyer-Ter-Vehn J, Tronnier A, Sokolowski-Tinten K, Stojanovic N, Tiedtke K, Toleikis S, Tschentscher T, Wabnitz H, Zastrau U. Characteristics of focused soft X-ray free-electron laser beam determined by ablation of organic molecular solids. Opt Express 2007; 15:6036-6043. [PMID: 19546907 DOI: 10.1364/oe.15.006036] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A linear accelerator based source of coherent radiation, FLASH (Free-electron LASer in Hamburg) provides ultra-intense femtosecond radiation pulses at wavelengths from the extreme ultraviolet (XUV; lambda<100nm) to the soft X-ray (SXR; lambda<30nm) spectral regions. 25-fs pulses of 32-nm FLASH radiation were used to determine the ablation parameters of PMMA - poly (methyl methacrylate). Under these irradiation conditions the attenuation length and ablation threshold were found to be (56.9+/-7.5) nm and approximately 2 mJ*cm(-2), respectively. For a second wavelength of 21.7 nm, the PMMA ablation was utilized to image the transverse intensity distribution within the focused beam at mum resolution by a method developed here.
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Affiliation(s)
- J Chalupský
- Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8, Czech Republic.
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Kaluza M, Schreiber J, Santala MIK, Tsakiris GD, Eidmann K, Meyer-Ter-Vehn J, Witte KJ. Influence of the laser prepulse on proton acceleration in thin-foil experiments. Phys Rev Lett 2004; 93:045003. [PMID: 15323768 DOI: 10.1103/physrevlett.93.045003] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2003] [Indexed: 05/24/2023]
Abstract
We investigate the influence of the laser prepulse due to amplified spontaneous emission on the acceleration of protons in thin-foil experiments. We show that changing the prepulse duration has a profound effect on the maximum proton energy. We find an optimal value for the target thickness, which strongly depends on the prepulse duration. At this optimal thickness, the rear side acceleration process leads to the highest proton energies, while this mechanism is rendered ineffective for thinner targets due to a prepulse-induced plasma formation at the rear side. In this case, the protons are primarily accelerated by the front side mechanism leading to lower cutoff energies.
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Affiliation(s)
- M Kaluza
- Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany
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Sheng ZM, Mima K, Sentoku Y, Jovanović MS, Taguchi T, Zhang J, Meyer-Ter-Vehn J. Stochastic heating and acceleration of electrons in colliding laser fields in plasma. Phys Rev Lett 2002; 88:055004. [PMID: 11863737 DOI: 10.1103/physrevlett.88.055004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2001] [Revised: 10/16/2001] [Indexed: 05/23/2023]
Abstract
We propose a mechanism that leads to efficient acceleration of electrons in plasma by two counterpropagating laser pulses. It is triggered by stochastic motion of electrons when the laser fields exceed some threshold amplitudes, as found in single-electron dynamics. It is further confirmed in particle-in-cell simulations. In vacuum or tenuous plasma, electron acceleration in the case with two colliding laser pulses can be much more efficient than with one laser pulse only. In plasma at moderate densities, such as a few percent of the critical density, the amplitude of the Raman-backscattered wave is high enough to serve as the second counterpropagating pulse to trigger the electron stochastic motion. As a result, even with one intense laser pulse only, electrons can be heated up to a temperature much higher than the corresponding laser ponderomotive potential.
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Affiliation(s)
- Z-M Sheng
- Institute of Laser Engineering, Osaka University, 2-6 Yamada-oka, Suita, Osaka 565-0871, Japan
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Shen B, Meyer-Ter-Vehn J. Pair and gamma-photon production from a thin foil confined by two laser pulses. Phys Rev E Stat Nonlin Soft Matter Phys 2002; 65:016405. [PMID: 11800788 DOI: 10.1103/physreve.65.016405] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2001] [Indexed: 05/23/2023]
Abstract
Electron-positron and gamma-photon production by high-intensity laser pulses is investigated for a special target geometry, in which two pulses irradiate a very thin foil (10-100 nm < skin depth) with same intensity from opposite sides. A stationary solution is derived describing foil compression between the two pulses. Circular polarization is chosen such that all electrons and positrons rotate in the plane of the foil. We discuss the laser and target parameters required in order to optimize the gamma photon and pair production rate. We find a gamma-photon intensity of 7x10(27)/sr s and a positron density of 5x10(22)/cm(3) when using two 330 fs, 7x10(21) W/cm(2) laser pulses.
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Affiliation(s)
- Baifei Shen
- Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany
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Honda M, Meyer-Ter-Vehn J, Pukhov A. Collective stopping and ion heating in relativistic-electron-beam transport for fast ignition. Phys Rev Lett 2000; 85:2128-2131. [PMID: 10970479 DOI: 10.1103/physrevlett.85.2128] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2000] [Indexed: 05/23/2023]
Abstract
Filamented transport of laser-generated relativistic electron beams in a plasma is studied with reference to fast ignition of fusion targets. The study is based on transverse two-dimensional particle-in-cell simulation. Coalescence of current filaments and related ion dynamics are found to determine beam stopping and ion heating.
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Affiliation(s)
- M Honda
- Max-Planck-Institut fur Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany
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Eidmann K, Meyer-Ter-Vehn J, Schlegel T, Huller S. Hydrodynamic simulation of subpicosecond laser interaction with solid-density matter. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 2000; 62:1202-1214. [PMID: 11088579 DOI: 10.1103/physreve.62.1202] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/1999] [Indexed: 05/23/2023]
Abstract
The interaction of ultrashort subpicosecond laser pulses with initially cold and solid matter is investigated in a wide intensity range (10(11) to 10(17) W/cm(2)) by means of the hydrodynamic code MULTI-FS, which is an extension of the long pulse version of MULTI [R. Ramis, R. Schmalz, and J. Meyer-ter-Vehn, Comput. Phys. Commun. 49, 475 (1988)]. Essential modifications for the treatment of ultrashort pulses are the solution of Maxwell's equations in a steep gradient plasma, consideration of the nonequilibrium between electrons and ions, and a model for the electrical and thermal conductivity covering the wide range from the solid state to the high temperature plasma. The simulations are compared with several absorption measurements performed with aluminum targets at normal and oblique incidence. Good agreement is obtained by an appropriate choice of the electron-ion energy exchange time (characterized by 10 to 20 ps in cold solid Al). In addition we discuss the intensity scaling of the temperature, of the pressure, and of the density, where the laser energy is deposited in the expanding plasma, as well as the propagation of the heat wave and the shock wave into the solid. For laser pulse durations >/=150 fs considered in this paper the amount of isochorically heated matter at solid density is determined by the depth of the electron heat wave in the whole intensity range.
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Affiliation(s)
- K Eidmann
- Max-Planck-Institut fur Quantenoptik, Hans Kopfermannstrasse 1, D-85748 Garching, Germany
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Shvets G, Fisch NJ, Pukhov A, Meyer-Ter-Vehn J. Generation of periodic accelerating structures in plasma by colliding laser pulses. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 1999; 60:2218-23. [PMID: 11970016 DOI: 10.1103/physreve.60.2218] [Citation(s) in RCA: 6] [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: 10/21/1998] [Indexed: 04/18/2023]
Abstract
A mechanism for generating large (>1 GeV/m) accelerating wakes in a plasma is proposed. Two slightly detuned counterpropagating laser beams, an ultrashort timing pulse and a long pump, exchange photons and deposit the recoil momentum in plasma electrons. This produces a localized region of electron current, which acts as a virtual electron beam, inducing intense plasma wakes with phase velocity equal to the group velocity of the short pulse. Modulating the pumping beam generates periodic accelerating structures in the plasma ("plasma linac") which can be used for particle acceleration unlimited by the dephasing between the particles and the wake. An important difference between this type of plasma accelerator and the conventional wakefield accelerators is that this type can be achieved with laser intensities I<<10(18) W/cm(2).
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Affiliation(s)
- G Shvets
- Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, USA
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Polishchuk AY, Meyer-Ter-Vehn J. Electron-ion relaxation in a plasma interacting with an intense laser field. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 1994; 49:663-666. [PMID: 9961259 DOI: 10.1103/physreve.49.663] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Abstract
The conversion of ion beam energy into thermal x-ray radiation by means of stretched cylindrical plasma volumes is studied by analytic modeling and numerical simulation. The analysis is restricted to one-dimensional radiation hydrodynamics. Scaling relations for different materials are derived. Due to equation-of-state properties, high-Z material turns out superior for achieving high conversion efficiency. The paper provides practical answers for thermal x-ray generation with intense heavy ion beams. Deposition powers in the order of 10l6 W/g are required for applications to ion beam inertial confinement fusion.
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Affiliation(s)
- M Murakami
- Max-Planck-Institut für Quantenoptik, D-8046 Garching, Federal Republic of Germany
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