Enhanced laser-driven proton acceleration via improved fast electron heating in a controlled pre-plasma
Authors: Gizzi LA., Boella E., Labate L., Baffigi F., Bilbao PJ., Brandi F., Cristoforetti G., Fazzi A., Fulgentini L., Giove D., Koester P., Palla D., Tomassini P.
Autors Affiliation: Intense Laser Irradiation Laboratory, INO-CNR, Pisa, Italy
INFN, Sez., Pisa, Italy
Physics Department, Lancaster University, Bailrigg, Lancaster, LA1 4YW, UK
Cockcroft Institute, Sci-Tech Daresbury, Keckwick Lane, Warrington, WA4 4AD, UK
Dipartimento di Energia, Politecnico di Milano, Milan, Italy
INFN, Sezione di Milano, Milan, Italy
INFN-LASA, Segrate, Italy
Abstract: The interaction of ultraintense laser pulses with solids is largely affected by the plasma gradient at the vacuum–solid interface, which modifies the absorption and ultimately, controls the energy distribution function of heated electrons. A micrometer scale-length plasma has been predicted to yield a significant enhancement of the energy and weight of the fast electron population and to play a major role in laser-driven proton acceleration with thin foils. We report on recent experimental results on proton acceleration from laser interaction with foil targets at ultra-relativistic intensities. We show a threefold increase of the proton cut-off energy when a micrometer scale-length pre-plasma is introduced by irradiation with a low energy femtosecond pre-pulse. Our realistic numerical simulations agree with the observed gain of the proton cut-off energy and confirm the role of stochastic heating of fast electrons in the enhancement of the accelerating sheath field.
Journal/Review: SCIENTIFIC REPORTS
Volume: 11 Pages from: 13728 to: 13728
KeyWords: relativistic laser-plasma interaction, proton accelerationDOI: https://doi.org/10.1038/s41598-021-93011-3