Filamentation effects and second-harmonic spectra in laser-produced plasmas

Journal Article · Sun Aug 01 04:00:00 EDT 1993 · Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; (United States)

DOI:https://doi.org/10.1103/PhysRevE.48.1337· OSTI ID:6272820

Khalfaoui, A H; Abdelli, S; Kerdja, T; Ghobrini, D ^[1]

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1. MDRTE, Centre de Developpement des Technologies Avancees 2, boulevard Frantz Fanon, Alger-gare, Boite Postale 1017, Alger 16000 (Algeria)

Sideway scattered second-harmonic spectra emitted from a 1064-nm-laser-produced plasma have been observed to originate from nonlinear coupling near the critical surface. The time evolution of the second-harmonic optical density confirmed the possibility that a plasmon issued from the resonant absorption of the incident beam can recombine with a photon ([omega][sub 0]) to give a transverse wave of frequency 2[omega][sub 0]. A plasmon issued from a parametric decay instability may also, by coalescence with an incident photon, give a transverse wave at a shifted second-harmonic frequency. The threshold of such a combination is determined. Moreover, irregular plasma-parameter variations and the perturbed spatial uniformity of the incident beam appear to alter the second-harmonic spectra. An oscillatory structure of the optical density of the observed second harmonic is interpreted as a result of the coupling physics involved and of laser-beam filamentation.

• OSTI ID: 6272820
• Journal Information: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; (United States), Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; (United States) Vol. 48:2; ISSN 1063-651X; ISSN PLEEE8
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700320 -- Plasma Diagnostic Techniques & Instrumentation-- (1992-)
700350* -- Plasma Production
Heating
Current Drive
& Interactions-- (1992-)
ABSORPTION
DATA ANALYSIS
EMISSION SPECTRA
LASER-PRODUCED PLASMA
NONLINEAR OPTICS
NONLINEAR PROBLEMS
OPACITY
OPTICAL PROPERTIES
OPTICS
PHYSICAL PROPERTIES
PLASMA
PLASMA DIAGNOSTICS
PLASMONS
QUASI PARTICLES
RESONANCE ABSORPTION
SORPTION
SPECTRA