Laser-to-hot-electron conversion limitations in relativistic laser matter interactions due to multi-picosecond dynamics

• DOI: 10.1063/1.4918332
• Publication Date: 2015-04-20T17:28:31Z
• Authors: M. Schollmeier; A. B. Sefkow; M. Geissel; A. V. Arefiev; K. A. Flippo; S. A. Gaillard; R. P. Johnson; M. W. Kimmel; D. T. Offermann; P. K. Rambo; J. Schwarz; T. Shimada
• Keywords: Picosecond; Relativistic plasma

High-energy short-pulse lasers are pushing the limits of plasma-based particle acceleration, x-ray generation, and high-harmonic generation by creating strong electromagnetic fields at laser focus where electrons being accelerated to relativistic velocities. Understanding electron dynamics is key for an accurate interpretation measurements. We present a unified self-consistent modeling approach in quantitative agreement with measurements differing trends across multiple target types acquired from two separate systems, which differ only their nanosecond picosecond-scale rising edge. Insights high-fidelity laser-plasma interaction demonstrate that ps-scale, orders magnitude weaker edge main pulse measurably alters evolution compared idealized shapes. This can lead instance experimentally observed difference between 45 MeV 75 maximum energy protons nominally identical shots, due ps-scale prepulse variations. Our results show realistic inclusion temporal profiles efforts required if predictive capability extrapolation sought future designs or other ion acceleration schemes.