Stimulated Raman backscatter in the kinetic regime of lasers with orbital angular momentum
ORAL
Abstract
Stimulated Raman scattering (SRS) in laser driven inertial confinement fusion (ICF) can result in decreased laser energy coupling to the target and reduced symmetry of the drive. There has been little research on SRS for lasers which carry orbital angular momentum (OAM). Any laser can scatter into a variety of different OAM modes and can drive a plasma wave which may also carry OAM. The OAM in the plasma wave can change the linear and nonlinear damping rates of the wave. In plasmas where the kλDe of the plasma wave is large, the linear and nonlinear damping of the plasma wave affects the growth of SRS. We present preliminary results of SRS of lasers with and without OAM for plasma conditions of interest to ICF using the envelope equation code pF3D and the particle-in-cell code OSIRIS. We examine cases where conditions are near threshold and far above threshold for the onset of SRS. We also investigate Raman amplification of a seed pulse for combinations of pumps and seeds with different or the same OAM.
–
Presenters
-
Sarah E Chase
University of California, Los Angeles
Authors
-
Sarah E Chase
University of California, Los Angeles
-
Benjamin J Winjum
University of California, Los Angeles
-
Frank S Tsung
University of California, Los Angeles
-
Kyle G Miller
Laboratory for Laser Energetics, University of Rochester, University of California, Los Angeles
-
Denise E Hinkel
LLNL, Lawrence Livermore National Laboratory, Lawrence Livermore Natl Lab
-
Warren B Mori
University of California, Los Angeles, Department of Physics and Astronomy, University of California, Los Angeles, CA 90095, USA