Proton acceleration by a pair of successive ultraintense femtosecond laser pulses
Journal article, 2018

We investigate the target normal sheath acceleration of protons in thin aluminum targets irradiated at a relativistic intensity by two time-separated ultrashort (35 fs) laser pulses. When the full-energy laser pulse is temporally split into two identical half-energy pulses, and using target thicknesses of 3 and 6 μm, we observe experimentally that the second half-pulse boosts the maximum energy and charge of the proton beam produced by the first half-pulse for time delays below ∼0.6-1 ps. Using two-dimensional particle-in-cell simulations, we examine the variation of the proton energy spectra with respect to the time-delay between the two pulses. We demonstrate that the expansion of the target front surface caused by the first pulse significantly enhances the hot-electron generation by the second pulse arriving after a few hundreds of fs time delay. This enhancement, however, does not suffice to further accelerate the fastest protons driven by the first pulse once three-dimensional quenching effects have set in. This implies a limit to the maximum time delay that leads to proton energy enhancement, which we theoretically determine.


Julien Ferri

Chalmers, Physics, Subatomic and Plasma Physics

L. Senje

Lund University

M. Dalui

Lund University

Krister Svensson

Lund University

B. Aurand

Lund University

M. Hansson

Lund University

A. Persson

Lund University

O. Lundh

Lund University

C.G. Wahlström

Lund University

Laurent Gremillet

The French Alternative Energies and Atomic Energy Commission (CEA)

Evangelos Siminos

University of Gothenburg

Timothy Dubois

Chalmers, Physics, Subatomic and Plasma Physics

Longqing Yi

Chalmers, Physics, Subatomic and Plasma Physics

Joana Luís Martins

Chalmers, Physics, Subatomic and Plasma Physics

Tünde Fülöp

Chalmers, Physics, Subatomic and Plasma Physics

Physics of Plasmas

1070-664X (ISSN) 1089-7674 (eISSN)

Vol. 25 4 043115

Subject Categories

Accelerator Physics and Instrumentation

Atom and Molecular Physics and Optics

Other Physics Topics



More information

Latest update

5/8/2018 9