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What is laser plasma?

  1. Nov 1, 2004 #1
    what is the Baisc of laser plasma??
    i just found about Laser-Plasma Interactions , but i would Know what is the theory of laser plasma and who was the first person studied this subjet??

    could any one help me!!
  2. jcsd
  3. Nov 1, 2004 #2


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    Some of the ideas of laser plasma interaction date back to the invention of the laser itself. One of the more interesting applications is in so-called Inertial Confinement Fusion which is an alternative to magnetic confinement fusion. The basic idea is to use extremely intense laser radiation (terawatts) to heat small pellets filled with deuterium to extremely high temperatures such that the outer shell will ablate producing a rocket like effect thereby causing the fuel-containing interior to compress.

    If the fuel is adequately compressed and heated then fusion can occur.

    The laser interaction goes far beyond mere heating. For one thing the laser intensities are high enough to place the interaction into the strong field inverse bremmstrahlung (heating) regime which means heating is less efficient.

    Fortunately, resonant coupling of the laser radiation with longitudinal electron plasma waves allows for efficient absorption of the laser light (linear wave conversion). Further, however, various types of stimulated scattering of laser light and other anomalous effect can occur at such elevated intensities including stimulated Raman (SRS) and Brilliouin (SBS)scattering (laser light interacting nonlinearly with electron plasma waves and ion acoustic waves respectively). Clearly, those will have adverse effects with the former (SRS) generating energetic electrons causing the core to heat prematurely making it more difficult to compress while the latter (SBS) can make the plasma reflect the laser light quite efficiently.
  4. Mar 6, 2008 #3

    Claude Bile

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    I've never heard of "laser plasma". Do you mean "laser generated plasma"?

    Laser induced breakdown occurs when you "jiggle" an atom so hard that you end up ripping electrons out of their orbitals and inducing absorption in normally transparent media. The generated plasma alters the propagation characteristics of the laser beam - most notably it induces something called filamentation, which is a balancing act between nonlinear Kerr self-focusing and defocusing induced by the generated plasma, and results in light not spreading out as it propagates, rather travelling as a confined "filament" of light. LIDAR (The light version of Radar) utilises this phenomenon to deliver power to a distant target with minimal loss.

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