Measurements of plasma-wave generation using a short-pulse high-intensity laser beat wave

Journal Article · Sun Jan 15 04:00:00 EST 2006 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.2160517· OSTI ID:20782466

Walton, B; Najmudin, Z; Wei, M S; Marle, C; Kingham, R J; Krushelnick, K; Dangor, A E; Clarke, R J; Poulter, M J; Hernandez-Gomez, C; Hawkes, S; Neely, D; Collier, J L; Danson, C N; Fritzler, S; Malka, V ^[1]

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1. Blackett Laboratory, Imperial College, London SW7 2BZ (United Kingdom)

Experiments to examine the generation of relativistic plasma waves via a high-intensity short-pulse beat-wave scheme are described in detail. The pulse stretcher of the Vulcan chirped-pulse amplification (CPA) laser system was modified to produce two frequency, 3 ps pulses focusable to intensities up to 10{sup 18} W cm{sup -2}. Short high-intensity pulses were used to avoid limitations to the plasma-wave amplitude due to the modulational instability. Two experiments were undertaken, at 3 and 10 TW, with the generation of plasma waves diagnosed by measuring the sidebands produced in the spectrum of the forward scattered beam. A resonance in the sideband signal was observed for an initial plasma density higher than expected for the given beat frequency. This resonance shift can be attributed to transverse ponderomotive expulsion of plasma electrons from the laser focal region. A monotonically increasing background was also observed, which was due to nonresonant cross-phase modulation.

• OSTI ID: 20782466
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 1 Vol. 13; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
AMPLITUDES
ELECTRONS
LASERS
LIGHT TRANSMISSION
PLASMA DENSITY
PLASMA DIAGNOSTICS
PLASMA INSTABILITY
PLASMA WAVES
PONDEROMOTIVE FORCE
PULSES
RELATIVISTIC PLASMA
RESONANCE