Plasma density ramp for relativistic self-focusing of an intense laser

Journal Article · Tue May 15 04:00:00 EDT 2007 · Journal of the Optical Society of America. Part B, Optical Physics

DOI:https://doi.org/10.1364/JOSAB.24.001155· OSTI ID:20929678

Gupta, Devki N; Hur, Min S; Hwang, Ilmoon; Suk, Hyyong; Sharma, Ashok K ^[1]

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1. Center for Advanced Accelerators, Korea Electrotechnology Research Institute, Changwon 641-120 (Korea, Republic of)

It is known that a high-power laser propagating through an underdense plasma can acquire a minimum spot size due to relativistic self-focusing. Beyond the focus, the nonlinear refraction starts weakening, and the spot size of the laser increases, showing periodic self-focusing/ defocusing behavior with the distance of propagation. To overcome the defocusing, we propose the introduction of a localized upward plasma density ramp. In the presence of an upward ramp of plasma density, the laser beam obtains a minimum spot size and maintains it with only a mild ripple. For suitable parameters of the laser and the plasma, we have deduced conditions for the self-focusing. This kind of plasma density ramp may be observed in a gas-jet plasma experiment and resembles a plasma lens.

• OSTI ID: 20929678
• Journal Information: Journal of the Optical Society of America. Part B, Optical Physics, Journal Name: Journal of the Optical Society of America. Part B, Optical Physics Journal Issue: 5 Vol. 24; ISSN JOBPDE; ISSN 0740-3224
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ELECTROMAGNETIC LENSES
FOCUSING
LASERS
LIGHT TRANSMISSION
NONLINEAR PROBLEMS
PERIODICITY
PLASMA
PLASMA DENSITY
REFRACTION
RELATIVISTIC RANGE