Coherent forward stimulated-brillouin scattering of a spatially incoherent laser beam in a plasma and its effect on beam spray.
نویسندگان
چکیده
A statistical model for forward stimulated-Brillouin scattering is developed for a spatially incoherent, monochromatic, laser beam propagating in a plasma. The threshold above which the laser beam spatial incoherence cannot prevent the coherent growth of forward stimulated-Brillouin scattering is computed. It is found to be well below the threshold for self-focusing. Three-dimensional simulations confirm its existence and reveal the onset of beam spray above it. From these results, we propose a new figure of merit for the control of propagation through a plasma of a spatially incoherent laser beam.
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عنوان ژورنال:
- Physical review letters
دوره 102 15 شماره
صفحات -
تاریخ انتشار 2009