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Title: On the physics of electron ejection from laser-irradiated overdense plasmas

Abstract

Using 1D and 2D PIC simulations, we describe and model the backward ejection of electron bunches when a laser pulse reflects off an overdense plasma with a short density gradient on its front side. The dependence on the laser intensity and gradient scale length is studied. It is found that during each laser period, the incident laser pulse generates a large charge-separation field, or plasma capacitor, which accelerates an attosecond bunch of electrons toward vacuum. This process is maximized for short gradient scale lengths and collapses when the gradient scale length is comparable to the laser wavelength. We develop a model that reproduces the electron dynamics and the dependence on laser intensity and gradient scale length. This process is shown to be strongly linked with high harmonic generation via the Relativistic Oscillating Mirror mechanism.

Authors:
; ;  [1]
  1. Laboratoire d'Optique Appliquée, ENSTA ParisTech, CNRS, Ecole Polytechnique, Université Paris-Saclay, 828 bd des Maréchaux, 91762 Palaiseau Cedex (France)
Publication Date:
OSTI Identifier:
22598943
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CAPACITORS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; DENSITY; ELECTRONS; HARMONIC GENERATION; IRRADIATION; LASERS; LENGTH; MIRRORS; ONE-DIMENSIONAL CALCULATIONS; PLASMA; PULSES; RELATIVISTIC RANGE; TWO-DIMENSIONAL CALCULATIONS; WAVELENGTHS

Citation Formats

Thévenet, M., Vincenti, H., and Faure, J. On the physics of electron ejection from laser-irradiated overdense plasmas. United States: N. p., 2016. Web. doi:10.1063/1.4954822.
Thévenet, M., Vincenti, H., & Faure, J. On the physics of electron ejection from laser-irradiated overdense plasmas. United States. doi:10.1063/1.4954822.
Thévenet, M., Vincenti, H., and Faure, J. 2016. "On the physics of electron ejection from laser-irradiated overdense plasmas". United States. doi:10.1063/1.4954822.
@article{osti_22598943,
title = {On the physics of electron ejection from laser-irradiated overdense plasmas},
author = {Thévenet, M. and Vincenti, H. and Faure, J.},
abstractNote = {Using 1D and 2D PIC simulations, we describe and model the backward ejection of electron bunches when a laser pulse reflects off an overdense plasma with a short density gradient on its front side. The dependence on the laser intensity and gradient scale length is studied. It is found that during each laser period, the incident laser pulse generates a large charge-separation field, or plasma capacitor, which accelerates an attosecond bunch of electrons toward vacuum. This process is maximized for short gradient scale lengths and collapses when the gradient scale length is comparable to the laser wavelength. We develop a model that reproduces the electron dynamics and the dependence on laser intensity and gradient scale length. This process is shown to be strongly linked with high harmonic generation via the Relativistic Oscillating Mirror mechanism.},
doi = {10.1063/1.4954822},
journal = {Physics of Plasmas},
number = 6,
volume = 23,
place = {United States},
year = 2016,
month = 6
}
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