Relativistic focusing and ponderomotive channeling of intense laser beams

Journal Article · Fri Sep 01 04:00:00 EDT 2000 · Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics

DOI:https://doi.org/10.1103/PhysRevE.62.4120· OSTI ID:20217625

Hafizi, B ^[1]; Ting, A ^[2]; Sprangle, P ^[2]; Hubbard, R F ^[2]

---

1. Icarus Research, Inc., P.O. Box 30780, Bethesda, Maryland 20824-0780 (United States)
2. Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375-5346 (United States)

The ponderomotive force associated with an intense laser beam expels electrons radially and can lead to cavitation in plasma. Relativistic effects as well as ponderomotive expulsion of electrons modify the refractive index. An envelope equation for the laser spot size is derived, using the source-dependent expansion method with Laguerre-Gaussian eigenfunctions, and reduced to quadrature. The envelope equation is valid for arbitrary laser intensity within the long pulse, quasistatic approximation and neglects instabilities. Solutions of the envelope equation are discussed in terms of an effective potential for the laser spot size. An analytical expression for the effective potential is given. For laser powers exceeding the critical power for relativistic self-focusing the analysis indicates that a significant contraction of the spot size and a corresponding increase in intensity is possible. (c) 2000 The American Physical Society.

• OSTI ID: 20217625
• Journal Information: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics Journal Issue: 3 Vol. 62; ISSN PLEEE8; ISSN 1063-651X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BEAM-PLASMA SYSTEMS
LASER RADIATION
PONDEROMOTIVE FORCE
REFRACTIVE INDEX
RELATIVISTIC PLASMA
THEORETICAL DATA