Source: https://www.nature.com/articles/s41566-019-0356-z?error=cookies_not_supported&code=6701be8f-187a-463c-b96f-65943042d609
Timestamp: 2019-04-24 20:19:02+00:00

Document:
Ultrafast pump–probe experiments open the possibility to track fundamental material behaviour, such as changes in electronic configuration, in real time. To date, most of these experiments are performed using an electron or a high-energy photon beam that is synchronized to an infrared laser pulse. Entirely new opportunities can be explored if not only a single, but multiple synchronized, ultrashort, high-energy beams are used. However, this requires advanced radiation sources that are capable of producing dual-energy electron beams, for example. Here, we demonstrate simultaneous generation of twin-electron beams from a single compact laser wakefield accelerator. The energy of each beam can be individually adjusted over a wide range and our analysis shows that the bunch lengths and their delay inherently amount to femtoseconds. Our proof-of-concept results demonstrate an elegant way to perform multi-beam experiments in the future on a laboratory scale.
Krausz, F. & Ivanov, M. Attosecond physics. Rev. Mod. Phys. 81, 163–234 (2009).
Kupitz, C. et al. Serial time-resolved crystallography of photosystem II using a femtosecond X-ray laser. Nature 513, 261–265 (2014).
Beaurepaire, E., Merle, J. C., Daunois, A. & Bigot, J.-Y. Ultrafast spin dynamics in ferromagnetic nickel. Phys. Rev. Lett. 76, 1–4 (1996).
Pertot, Y. et al. Time-resolved X-ray absorption spectroscopy with a water window high-harmonic source. Science 355, 264–267 (2017).
Rousse, A. et al. Non-thermal melting in semiconductors measured at femtosecond resolution. Nature 410, 65–68 (2001).
Sciaini, G. & Miller, R. J. D. Femtosecond electron diffraction: heralding the era of atomically resolved dynamics. Rep. Prog. Phys. 74, 096101 (2011).
Cavalleri, A. et al. Tracking the motion of charges in a terahertz light field by femtosecond X-ray diffraction. Nature 442, 664–666 (2006).
Bressler, C. & Chergui, M. Ultrafast X-ray absorption spectroscopy. Chem. Rev. 104, 1781–1812 (2004).
Chergui, M. & Collet, E. Photoinduced structural dynamics of molecular systems mapped by time-resolved X-ray methods. Chem. Rev. 117, 11025–11065 (2017).
Rousse, A., Rischel, C. & Gauthier, J. C. Colloquium: femtosecond X-ray crystallography. Rev. Mod. Phys. 73, 17–31 (2001).
Bostedt, C. et al. Linac coherent light source: the first five years. Rev. Mod. Phys. 88, 015007 (2016).
Schoenlein, R. W. et al. Generation of femtosecond pulses of synchrotron radiation. Science 287, 2237–2240 (2000).
McNeil, B. W. J. & Thompson, N. R. X-ray free-electron lasers. Nat. Photon. 4, 814–821 (2010).
Pellegrini, C. X-ray free-electron lasers: from dreams to reality. Phys. Scr. T169, 014004 (2016).
Esarey, E., Schroeder, C. B. & Leemans, W. P. Physics of laser-driven plasma-based electron accelerators. Rev. Mod. Phys. 81, 1229–1285 (2009).
Lundh, O. et al. Few femtosecond, few kiloampere electron bunch produced by a laser–plasma accelerator. Nat. Phys. 7, 219–222 (2011).
Malka, V. et al. Electron acceleration by a wake field forced by an intense ultrashort laser pulse. Science 298, 1596–1600 (2002).
Leemans, W. P. et al. GeV electron beams from a centimetre-scale accelerator. Nat. Phys. 2, 696–699 (2006).
Leemans, W. et al. Observation of Terahertz emission from a laser-plasma accelerated electron bunch crossing a plasma-vacuum boundary. Phys. Rev. Lett. 91, 074802 (2003).
Fuchs, M. et al. Laser-driven soft-X-ray undulator source. Nat. Phys. 5, 826–829 (2009).
Khrennikov, K. et al. Tunable all-optical quasimonochromatic thomson X-ray source in the nonlinear regime. Phys. Rev. Lett. 114, 195003 (2015).
Döpp, A. et al. Stable femtosecond X-rays with tunable polarization from a laser-driven accelerator. Light Sci. Appl. 6, e17086 (2017).
Yan, W. et al. High-order multiphoton Thomson scattering. Nat. Photon. 11, 514–520 (2017).
Fourmaux, S. et al. Single shot phase contrast imaging using laser-produced Betatron X-ray beams. Opt. Lett. 36, 2426–2428 (2011).
Kneip, S. et al. X-ray phase contrast imaging of biological specimens with femtosecond pulses of betatron radiation from a compact laser plasma wakefield accelerator. Appl. Phys. Lett. 99, 093701 (2011).
Mahieu, B. et al. Probing warm dense matter using femtosecond X-ray absorption spectroscopy with a laser-produced betatron source. Nat. Commun. 9, 3276 (2018).
Wood, J. C. et al. Ultrafast imaging of laser driven shock waves using betatron X-rays from a laser wakefield accelerator. Sci. Rep. 8, 11010 (2018).
Allaria, E. et al. Two-colour pump–probe experiments with a twin-pulse-seed extreme ultraviolet free-electron laser. Nat. Commun. 4, 2476 (2013).
Bencivenga, F. et al. Four-wave mixing experiments with extreme ultraviolet transient gratings. Nature 520, 205–208 (2015).
Ferrari, E. Seeded multicolor FEL pulses: status and future plans. Synchrotron Radiat. News 29, 4–9 (2016).
Hemsing, E., Stupakov, G., Xiang, D. & Zholents, A. Beam by design: laser manipulation of electrons in modern accelerators. Rev. Mod. Phys. 86, 897–941 (2014).
Ferrari, E. et al. Widely tunable two-colour seeded free-electron laser source for resonant-pump resonant-probe magnetic scattering. Nat. Commun. 7, 10343 (2015).
Hara, T. et al. Two-colour hard X-ray free-electron laser with wide tunability. Nat. Commun. 4, 2919 (2013).
Marinelli, A. et al. High-intensity double-pulse X-ray free-electron laser. Nat. Commun. 6, 6369 (2015).
Ronsivalle, C. et al. Large-bandwidth two-color free-electron laser driven by a comb-like electron beam. New J. Phys. 16, 033018 (2014).
Malka, V. Laser plasma accelerators. Phys. Plasmas 19, 055501 (2012).
Corde, S. et al. Observation of longitudinal and transverse self-injections in laser-plasma accelerators. Nat. Commun. 4, 1501 (2013).
Mirzaie, M. et al. Demonstration of self-truncated ionization injection for GeV electron beams. Sci. Rep. 5, 14659 (2015).
Walker, P. A. et al. Investigation of GeV-scale electron acceleration in a gas-filled capillary discharge waveguide. New J. Phys. 15, 045024 (2013).
Lundh, O., Rechatin, C., Lim, J., Malka, V. & Faure, J. Experimental measurements of electron-bunch trains in a laser-plasma accelerator. Phys. Rev. Lett. 110, 065005 (2013).
Zeng, M. et al. Multichromatic narrow-energy-spread electron bunches from laser-wakefield acceleration with dual-color lasers. Phys. Rev. Lett. 114, 084801 (2015).
Faure, J. et al. Controlled injection and acceleration of electrons in plasma wakefields by colliding laser pulses. Nature 444, 737–739 (2006).
Schmid, K. et al. Density-transition based electron injector for laser driven wakefield accelerators. Phys. Rev. Accel. Beams 13, 091301 (2010).
Buck, A. et al. Shock-front injector for high-quality laser-plasma acceleration. Phys. Rev. Lett. 110, 185006 (2013).
Fubiani, G., Esarey, E., Schroeder, C. B. & Leemans, W. P. Beat wave injection of electrons into plasma waves using two interfering laser pulses. Phys. Rev. E 70, 016402 (2004).
Davoine, X., Lefebvre, E., Rechatin, C., Faure, J. & Malka, V. Cold optical injection producing monoenergetic, multi-GeV electron bunches. Phys. Rev. Lett. 102, 065001 (2009).
Lehe, R., Lifschitz, A. F., Davoine, X., Thaury, C. & Malka, V. Optical transverse injection in laser-plasma acceleration. Phys. Rev. Lett. 111, 085005 (2013).
Lu, W. et al. Generating multi-GeV electron bunches using single stage laser wakefield acceleration in a 3D nonlinear regime. Phys. Rev. Accel. Beams 10, 061301 (2007).
Rechatin, C. et al. Controlling the phase-space volume of injected electrons in a laser-plasma accelerator. Phys. Rev. Lett. 102, 164801 (2009).
Thomas, A. G. R. Scalings for radiation from plasma bubbles. Phys. Plasmas 17, 056798 (2010).
Fubiani, G., Esarey, E., Schroeder, C. B. & Leemans, W. P. Improvement of electron beam quality in optical injection schemes using negative plasma density gradients. Phys. Rev. E 73, 026402 (2006).
Xu, J. et al. Dynamics of electron injection in a laser-wakefield accelerator. Phys. Plasmas 24, 083106 (2017).
Heigoldt, M. et al. Temporal evolution of longitudinal bunch profile in a laser wakefield accelerator. Phys. Rev. Accel. Beams 18, 121302 (2015).
He, Z. H. et al. Capturing structural dynamics in crystalline silicon using chirped electrons from a laser wakefield accelerator. Sci. Rep. 6, 36224 (2016).
Gauduel, Y. A., Glinec, Y., Rousseau, J. P., Burgy, F. & Malka, V. High energy radiation femtochemistry of water molecules: early electron-radical pairs processes. Eur. Phys. J. D 60, 121–135 (2010).
Petrillo, V. et al. Dual color X rays from Thomson or Compton sources. Phys. Rev. Accel. Beams 17, 020706 (2014).
Kalmykov, S. Y., Davoine, X., Ghebregziabher, I. & Shadwick, B. A. Customizable electron beams from optically controlled laser plasma acceleration for γ-ray sources based on inverse Thomson scattering. Nucl. Instrum. Methods Phys. Res. A 829, 52–57 (2016).
Kalmykov, S. Y., Davoine, X., Ghebregziabher, I. & Shadwick, B. A. Optically controlled laser–plasma electron accelerator for compact gamma-ray sources. New J. Phys. 20, 023047 (2018).
Corde, S. et al. Femtosecond X rays from laser-plasma accelerators. Rev. Mod. Phys. 85, 1–48 (2013).
Rykovanov, S. G., Geddes, C. G. R., Schroeder, C. B., Esarey, E. & Leemans, W. P. Controlling the spectral shape of nonlinear Thomson scattering with proper laser chirping. Phys. Rev. Accel. Beams 19, 1039 (2016).
Ta Phuoc, K. et al. All-optical Compton gamma-ray source. Nat. Photon. 6, 308–311 (2012).
Thomas, A. G. R. et al. Measurements of wave-breaking radiation from a laser-wakefield accelerator. Phys. Rev. Lett. 98, 054802 (2007).
Blumenfeld, I. et al. Energy doubling of 42 GeV electrons in a metre-scale plasma wakefield accelerator. Nature 445, 741–744 (2007).
Döpp, A. et al. Energy-chirp compensation in a laser wakefield accelerator. Phys. Rev. Lett. 121, 074802 (2018).
Manahan, G. G. et al. Single-stage plasma-based correlated energy spread compensation for ultrahigh 6D brightness electron beams. Nat. Commun. 8, 15705 (2017).
Rechatin, C. et al. Observation of beam loading in a laser–plasma accelerator. Phys. Rev. Lett. 103, 194804 (2009).
Hidding, B. et al. Monoenergetic energy doubling in a hybrid laser-plasma wakefield accelerator. Phys. Rev. Lett. 104, 195002 (2010).
Sundström, V. Femtobiology. Annu. Rev. Phys. Chem. 59, 53–77 (2008).
Zewail, A. H. Femtochemistry: atomic-scale dynamics of the chemical bond. J. Phys. Chem. A 104, 5660–5694 (2000).
Ullrich, J., Rudenko, A. & Moshammer, R. Free-electron lasers: new avenues in molecular physics and photochemistry. Annu. Rev. Phys. Chem. 63, 635–660 (2012).
Sears, C. M. S. et al. A high resolution, broad energy acceptance spectrometer for laser wakefield acceleration experiments. Rev. Sci. Instrum. 81, 073304 (2010).
Shaw, B. H., Steinke, S., van Tilborg, J. & Leemans, W. P. Reflectance characterization of tape-based plasma mirrors. Phys. Plasmas 23, 063118 (2016).
Götzfried, J. et al. Research towards high-repetition rate laser-driven X-ray sources for imaging applications. Nucl. Instrum. Methods Phys. Res. A 909, 1–4 (2018).
Lifschitz, A. et al. Particle-in-cell modelling of laser-plasma interaction using Fourier decomposition. J. Comput. Phys. 228, 1803–1814 (2009).
Swanson, K. K. et al. Control of tunable, monoenergetic laser-plasma-accelerated electron beams using a shock-induced density downramp injector. Phys. Rev. Accel. Beams 20, 051301 (2017).
Andriyash, I. A., Lehe, R. & Malka, V. A spectral unaveraged algorithm for free electron laser simulations. J. Comput. Phys. 282, 397–409 (2015).
This work was supported by DFG through the Cluster of Excellence Munich-Centre for Advanced Photonics (MAP EXC 158), DFG-Project Transregio TR-18 funding schemes, by EURATOM-IPP and the Max-Planck-Society. L.V. acknowledges the support by a grant from the Swedish Research Council (2016-05409). The authors thank F. Krausz for helpful comments. A.D. thanks I. Andriyash (WIS) for support with Chimera.
These authors contributed equally: J. Wenz, A. Döpp, K. Khrennikov.
A.B., M.H., K.K., J.W., J.X., L.V. and S.K. performed the experiments with ATLAS-60 at the MPQ. A.D., H.D., M.F.G., J.G., S.S. and S.K. performed the experiments with the upgraded laser system at LEX Photonics. A.D., K.K., S.S. and J.W. analysed the experimental data. A.D. performed PIC simulations, radiation and beam transport calculations. A.D., W.H., K.K., J.W., L.V. and S.K. discussed the results. A.D., K.K. and J.W. wrote the paper. S.K. supervised the project.
Correspondence to A. Döpp or S. Karsch.
Further experimental data as well as discussions about electron bunch delay, possible applications and beam transport.

References: V. 
 V. 
 V. 
 V. 
 V. 
 V. 
 V. 
 V. 
 V.