Nonlinear Scattering of Laser Light in Plasma Described by Geometric Optics

Dr. Jason Myatt

Goergen 101

Abstract

In laser-driven inertial-confinement-fusion (ICF) schemes, the energy contained in an intense, partially coherent, laser pulse is transferred to the kinetic energy of an imploding (spherically converging) shell. On stagnation, the deuterium-tritium fuel assembly reaches temperatures and densities such that thermonuclear fusion reactions occur. The goal of ICF research is to release more energy from these reactions that the energy expended to create them. The efficiency with which the laser energy is absorbed in the coronal plasma that surrounds to target is obviously of great importance. Quite recently, it has been discovered that a scattering instability arises during propagation of the laser light through the corona which significantly reduces this efficiency. In trying to understand this, we have been led to account for certain wave properties of light (e.g., polarization, partial coherence) in the framework geometric optics (ray-tracing). This is because ray-tracing algorithms are used in radiation-hydrodynamics simulation codes to simulate ICF implosions. I will describe why this is necessary, emphasizing aspects that may be familiar/interesting to members of the Institute of Optics.

Bio

Dr. Jason Myatt is Senior Scientist and Plasma Physics Group Leader at the Laboratory for Laser Energetics of the University of Rochester. His areas of research span a range of topics that include high intensity laser-matter interactions, high-energy-density physics, and laser-plasma interactions in the context of inertial confinement fusion.

Location: Goergen 101

Refreshments will be served.