High repetition-rate wakefield electron source generated by few-millijoule, 30 fs laser pulses on a density downramp

We report on an experimental demonstration of laser wakefield electron acceleration using a sub-TW power laser by tightly focusing 30 fs laser pulses with an 8 mJ pulse energy on a 100 μm scale gas target. The experiments are carried out at an unprecedented 0.5 kHz repetition rate, allowing ‘real-time’ optimization of accelerator parameters. Well-collimated and stable electron beams with quasi-monoenergetic peaks in the 100 keV range are measured. Particle-in-cell simulations show excellent agreement with the experimental results and suggest an acceleration mechanism based on electron trapping on the density downramp, due to the time-varying phase velocity of the plasma waves.

[1]  Môri,et al.  Wave-breaking amplitude of relativistic oscillations in a thermal plasma. , 1988, Physical review letters.

[2]  Victor Malka,et al.  Injection and acceleration of quasimonoenergetic relativistic electron beams using density gradients at the edges of a plasma channel , 2010 .

[3]  N. Andreev,et al.  Self-modulation of laser pulses in plasma and laser acceleration of electrons , 1995 .

[4]  J. Meyer-ter-Vehn,et al.  Laser wake field acceleration: the highly non-linear broken-wave regime , 2002 .

[5]  O. J. Luiten,et al.  Longitudinal phase-space manipulation of ellipsoidal electron bunches in realistic fields , 2006 .

[6]  G. Whitham,et al.  Linear and Nonlinear Waves , 1976 .

[7]  S. M. Wiggins,et al.  Low emittance, high brilliance relativistic electron beams from a laser-plasma accelerator. , 2010, Physical review letters.

[8]  S. V. Bulanov,et al.  Controlled electron injection into the wake wave using plasma density inhomogeneity , 2008 .

[9]  J. Cary,et al.  High-quality electron beams from a laser wakefield accelerator using plasma-channel guiding , 2004, Nature.

[10]  John M. Dawson,et al.  Nonlinear Electron Oscillations in a Cold Plasma , 1959 .

[11]  Ricardo Fonseca,et al.  Electron trapping and acceleration on a downward density ramp: a two-stage approach , 2010 .

[12]  Ferenc Krausz,et al.  Density-transition based electron injector for laser driven wakefield accelerators , 2010 .

[13]  J. Cary,et al.  Plasma-density-gradient injection of low absolute-momentum-spread electron bunches. , 2008, Physical review letters.

[14]  V Malka,et al.  Controlling the phase-space volume of injected electrons in a laser-plasma accelerator. , 2009, Physical review letters.

[15]  Christopher I. Moore,et al.  Plasma wakefield generation and electron acceleration in a self-modulated laser wakefield accelerator experiment* , 1997 .

[16]  M. Hashida,et al.  Single-shot ultrafast electron diffraction with a laser-accelerated sub-MeV electron pulse , 2009 .

[17]  Wiedemann,et al.  Generation and measurement of 50-fs(rms) electron pulses. , 1994, Physical review letters.

[18]  John M. Dawson,et al.  Forward Raman instability and electron acceleration , 1981 .

[19]  Eric Esarey,et al.  Overview of plasma-based accelerator concepts , 1996 .

[20]  V. Lobastov,et al.  Four-dimensional ultrafast electron microscopy. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[21]  Bergmann,et al.  Breaking of resonantly excited electron plasma waves. , 1993, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[22]  D. Pestrikov.  Erratum: Natural BNS damping of the fast ion instability [Phys. Rev. ST Accel. Beams 2, 044403 (1999)] , 2001 .

[23]  T. Tajima,et al.  Laser Electron Accelerator , 1979 .

[24]  Y. Glinec,et al.  A laser–plasma accelerator producing monoenergetic electron beams , 2004, Nature.

[25]  Vladimir A. Lobastov,et al.  Ultrafast electron diffraction (UED) a new development for the 4D determination of transient molecular structures , 2003 .

[26]  R. Fonseca,et al.  Measurements of the critical power for self-injection of electrons in a laser wakefield accelerator. , 2009, Physical review letters.

[27]  S. V. Bulanov,et al.  Particle injection into the wave acceleration phase due to nonlinear wake wave breaking , 1998 .

[28]  Rosenzweig.  Trapping, thermal effects, and wave breaking in the nonlinear plasma wake-field accelerator. , 1988, Physical review. A, General physics.

[29]  P. Cochat,et al.  Et al , 2008, Archives de pediatrie : organe officiel de la Societe francaise de pediatrie.

[30]  K. Nakamura,et al.  GeV electron beams from a centimetre-scale accelerator , 2006 .

[31]  Andrew G. Glen,et al.  APPL , 2001 .

[32]  Characterization of the beam loading effects in a laser plasma accelerator , 2010 .

[33]  S R Nagel,et al.  Near-GeV acceleration of electrons by a nonlinear plasma wave driven by a self-guided laser pulse. , 2009, Physical review letters.

[34]  Teruyoshi Takahashi,et al.  Calibration of imaging plate for high energy electron spectrometer , 2005 .

[35]  Nakajima,et al.  Observation of ultrahigh gradient electron acceleration by a self-modulated intense short laser pulse. , 1995, Physical review letters.

[36]  A. E. Dangor,et al.  Electron acceleration from the breaking of relativistic plasma waves , 1995, Nature.

[37]  G. Whitham.  Linear and non linear waves , 1974 .

[38]  I. V. Glazyrin,et al.  Quasimonoenergetic electron beams with relativistic energies and ultrashort duration from laser-solid interactions at 0.5 kHz. , 2009, Physical review letters.

[39]  A. E. Dangor,et al.  Monoenergetic beams of relativistic electrons from intense laser–plasma interactions , 2004, Nature.