Modeling ultrafast shadowgraphy in laser-plasma interaction experiments
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
Ultrafast shadowgraphy is a new experimental technique that uses few cycle laser pulses to image
density gradients in a rapidly evolving plasma. It enables structures that move at speeds close to
the speed of light, such as laser driven wakes, to be visualized. Here we study the process of shadowgraphic
image formation during the propagation of a few cycle probe pulse transversely through
a laser-driven wake using three-dimensional particle-in-cell simulations. In order to construct synthetic
shadowgrams a near-field snapshot of the ultrashort probe pulse is analyzed by means of
Fourier optics, taking into account the effect of a typical imaging setup. By comparing synthetic
and experimental shadowgrams we show that the generation of synthetic data is crucial for the correct
interpretation of experiments. Moreover, we study the dependence of synthetic shadowgrams
on various parameters such as the imaging system aperture, the position of the object plane and
the probe pulse delay, duration and wavelength. Finally, we show that time-dependent information
from the interaction can be recovered from a single shot by using a broadband, chirped probe pulse
and subsequent spectral filtering.
density gradients in a rapidly evolving plasma. It enables structures that move at speeds close to
the speed of light, such as laser driven wakes, to be visualized. Here we study the process of shadowgraphic
image formation during the propagation of a few cycle probe pulse transversely through
a laser-driven wake using three-dimensional particle-in-cell simulations. In order to construct synthetic
shadowgrams a near-field snapshot of the ultrashort probe pulse is analyzed by means of
Fourier optics, taking into account the effect of a typical imaging setup. By comparing synthetic
and experimental shadowgrams we show that the generation of synthetic data is crucial for the correct
interpretation of experiments. Moreover, we study the dependence of synthetic shadowgrams
on various parameters such as the imaging system aperture, the position of the object plane and
the probe pulse delay, duration and wavelength. Finally, we show that time-dependent information
from the interaction can be recovered from a single shot by using a broadband, chirped probe pulse
and subsequent spectral filtering.
Date Issued
2016-05-04
Date Acceptance
2016-03-23
Citation
Plasma Physics and Controlled Fusion, 2016, 58 (6)
ISSN
1361-6587
Publisher
IOP Publishing
Journal / Book Title
Plasma Physics and Controlled Fusion
Volume
58
Issue
6
Copyright Statement
© 2016 IOP Publishing Ltd. This is an author-created, un-copyedited version of an article accepted for publication in Plasma Physics and Controlled Fusion. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The definitive publisher authenticated version is available online at
Sponsor
The Royal Society
Science and Technology Facilities Council
Grant Number
UF110105
ST/P000835/1
Subjects
Science & Technology
Physical Sciences
Physics, Fluids & Plasmas
Physics, Nuclear
Physics
laser wakefield acceleration
imaging
Fourier optics
femtosecond shadowgraphy
OVERDENSE PLASMAS
ELECTRON-BEAMS
WAVE
TRANSPARENCY
WAKE
Fluids & Plasmas
0202 Atomic, Molecular, Nuclear, Particle And Plasma Physics
Publication Status
Accepted