5-10 May 2019
MedILS
Europe/Berlin timezone

Flying Focus and its application to Laser-Plasma Accelerators

7 May 2019, 12:00
30m
Main Hall (MedILS)

Main Hall

MedILS

Oral Contribution Plenary session

Speaker

Jessica Shaw (LLE)

Description

A chromatic focusing system combined with chirped laser pulses was used to create a “flying focus” [1]. This advanced focusing scheme provides unprecedented spatiotemporal control over the laser focal volume by enabling a small-diameter laser focus to propagate over 100 times its Rayleigh length. Furthermore, the flying focus decouples the speed at which the peak intensity propagates from the group velocity of the laser pulse, allowing the laser focus to co- or counter-propagate along its axis at any velocity. Experiments have demonstrated a nearly constant intensity over 4.5 mm while the velocity of the focus ranged from subluminal (0.01c) to superluminal (15c). When increasing the laser intensity above the ionization threshold of the background gas, an ionization wave was measured to track the ionization threshold intensity isosurface as it propagated and ionization waves of arbitrary velocity were demonstrated [2,3]. Subluminal and superluminal ionization fronts were produced over the entire 4.5 mm, both forward- and backward-propagating relative to the ionizing laser. All backward and all superluminal cases mitigated the issue of ionization-induced refraction, which typically challenges the formation of long, contiguous plasma channels. The properties of the flying focus provide the opportunity to overcome dephasing in laser-plasma accelerators, but theory predicts that the overall acceleration length will remain the same. Flying focus also presents a path around current fundamental limitations in laser-plasma amplifiers [4], photon accelerators, ion accelerators, THz generation, and high-order frequency conversion.

This material is based upon work supported by the U.S. Department of Energy/National Science Foundation under Award # DE-SC0017950, the U.S. Department of Energy Office of Fusion Energy Sciences under Award # DE-SC0016253, the Department of Energy National Nuclear Security Administration under Award # DE-NA0001944, the University of Rochester, and the New York State Energy Research and Development Authority

Working group Invited plenary talk

Primary author

Co-authors

Dr John Palastro (Laboratory for Laser Energetics, University of Rochester) Dr David Turnbull (Laboratory for Laser Energetics, University of Rochester) Dr Seung-Whan Bahk (Laboratory for Laser Energetics, University of Rochester) Dr Ildar Begishev (Laboratory for Laser Energetics, University of Rochester) Dr Robert Boni (Laboratory for Laser Energetics, University of Rochester) Dr Jake Bromage (Laboratory for Laser Energetics, University of Rochester) Ms Sara Bucht (Laboratory for Laser Energetics, University of Rochester) Mr Andrew Davies (Laboratory for Laser Energetics, University of Rochester) Dr Russell Follett (Laboratory for Laser Energetics, University of Rochester) Mr Philip Franke (Laboratory for Laser Energetics, University of Rochester) Dr Daniel Haberberger (Laboratory for Laser Energetics, University of Rochester) Mr Joseph Katz (Laboratory for Laser Energetics, University of Rochester) Dr Terrance Kessler (Laboratory for Laser Energetics, University of Rochester) Mr Avram Milder (Laboratory for Laser Energetics, University of Rochester) Dr Dustin Froula (Laboratory for Laser Energetics, University of Rochester)

Presentation Materials