TY - JOUR
T1 - Plasma density gratings induced by intersecting laser pulses in underdense plasmas
AU - Sheng, Z. M.
AU - Zhang, J.
AU - Umstadter, D.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2003/11
Y1 - 2003/11
N2 - Electron and ion density gratings induced by two intersecting ultrashort laser pulses at intensities of 1016 W/cm2 or lower are investigated. The ponderomotive force generated by the inhomogeneous intensity distribution in the intersecting region of the interfering pulses produces deep electron and ion density modulations at a wavelength less than a laser wave-length in vacuum. Dependence of the density modulation on the plasma densities, temperatures, and the ion mass, as well as the laser pulse parameters are studied analytically and by particle-in-cell simulations. It is found that the density peaks of such gratings can be a few times that of the initial plasma density and last as long as a few picoseconds. It is also demonstrated that the scattering of signal pulses by such a bulk density grating results in high-harmonic generation. The density gratings may be incorporated into ion-ripple lasers [K.R. Chen and J.M. Dawson, Phys. Rev. Lett. 68, 29 (1992)] to generate ultrashort X-ray pulses of a few angstroms by using electron beams at only a few tens of MeV only.
AB - Electron and ion density gratings induced by two intersecting ultrashort laser pulses at intensities of 1016 W/cm2 or lower are investigated. The ponderomotive force generated by the inhomogeneous intensity distribution in the intersecting region of the interfering pulses produces deep electron and ion density modulations at a wavelength less than a laser wave-length in vacuum. Dependence of the density modulation on the plasma densities, temperatures, and the ion mass, as well as the laser pulse parameters are studied analytically and by particle-in-cell simulations. It is found that the density peaks of such gratings can be a few times that of the initial plasma density and last as long as a few picoseconds. It is also demonstrated that the scattering of signal pulses by such a bulk density grating results in high-harmonic generation. The density gratings may be incorporated into ion-ripple lasers [K.R. Chen and J.M. Dawson, Phys. Rev. Lett. 68, 29 (1992)] to generate ultrashort X-ray pulses of a few angstroms by using electron beams at only a few tens of MeV only.
UR - http://www.scopus.com/inward/record.url?scp=0344741561&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0344741561&partnerID=8YFLogxK
U2 - 10.1007/s00340-003-1324-2
DO - 10.1007/s00340-003-1324-2
M3 - Article
AN - SCOPUS:0344741561
VL - 77
SP - 673
EP - 680
JO - Applied Physics B: Lasers and Optics
JF - Applied Physics B: Lasers and Optics
SN - 0946-2171
IS - 6-7
ER -