Statistical spatial properties of speckle patterns generated by multiple laser beams
- CEA, DAM, CESTA, BP 2, F-33114 Le Barp (France)
- CEA, DAM, DIF, F-91297 Arpajon (France)
This paper investigates hot spot characteristics generated by the superposition of multiple laser beams. First, properties of speckle statistics are studied in the context of only one laser beam by computing the autocorrelation function. The case of multiple laser beams is then considered. In certain conditions, it is shown that speckles have an ellipsoidal shape. Analytical expressions of hot spot radii generated by multiple laser beams are derived and compared to numerical estimates made from the autocorrelation function. They are also compared to numerical simulations performed within the paraxial approximation. Excellent agreement is found for the speckle width as well as for the speckle length. Application to the speckle patterns generated in the Laser MegaJoule configuration in the zone where all the beams overlap is presented. Influence of polarization on the size of the speckles as well as on their abundance is studied.
- OSTI ID:
- 22043416
- Journal Information:
- Physics of Plasmas, Vol. 18, Issue 8; Other Information: (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Subwavelength spatial correlations in near-field speckle patterns
Stimulated Brillouin scattering reduction induced by self-focusing for a single laser speckle interacting with an expanding plasma