NEWS | Nov. 13, 2013

Dr. Andrew Schmitt Elected American Physical Society Fellow

By Daniel Parry

U.S. Naval Research Laboratory (NRL) research physicist, Dr. Andrew Schmitt, is elected Fellow by the American Physical Society (APS) for major contributions to the theory and simulation of laser plasma interactions. Schmitt is further recognized for his pioneering work on the effects of laser beam smoothing and for advancing high-resolution simulations of laser high-gain direct-drive implosions.

Dr. Schmitt has made major contributions to the physics of laser-plasma interactions, to the development of a unique radiation hydrodynamics code, and to the understanding and development of high-performance direct-drive pellet designs, said Dr. Stephen Obenschain, head of the Laser Plasma Branch in the Plasma Physics Division. For nearly three decades, Dr. Schmitt has been conducting theoretical and computational research in laser target interactions at NRL and presently leads that effort.

Head of the Laser Fusion Theory Section at NRL, Schmitt has made seminal contributions to the understanding of the interaction of a laser utilizing beam smoothing with a plasma, development of a uniquely capable radiation hydrocode used for Inertial confinement fusion (ICF) simulations, the utilization of the hydrocode to simulate laser direct-drive implosions with high spatial resolution, and design of high-gain directly driven targets.

Early in his career Schmitt created a code to analyze illumination nonuniformity by raytracing light in arbitrary spherical plasmas and used it to discover a general rule that would produce perfect illumination of spherical ICF pellets with a limited number of beams.

His discovery led to a 3D time-dependent numerical laser propagation model that showed that optical smoothing methods would greatly reduce or eliminate filamentation of light. This model led to the discovery of plasma-induced incoherence (beam spraying) via forward-stimulated Brillouin scattering and inspired the creation of numerous similar laser-plasma interaction codes around the world.

Schmitt has also played a key role, individually and in collaboration with researchers from NRL and other major ICF laboratories, in developing simulations of both conventional and shock-ignited direct-drive target designs. At NRL he helped develop a unique (sliding-zone Eulerian) massively parallel 3D radiation-burn hydrocode (FASTRAD3D), adding physics packages such as multi-group alpha particle transport and more sophisticated laser propagation and absorption treatments.

This enabled Schmitt and fellow researchers to produce higher confidence simulations of laser plasma interactions, and in recent simulations has advanced the designs for robust shock ignited targets that are predicted to produce high enough thermonuclear gain for the energy application. He has also performed the first full-scale high-resolution implosion simulations of directly driven pellets that could resolve relevant Rayleigh-Taylor (RT) instability structure at the ablation surface.

The APS is a non-profit membership organization working to advance and diffuse the knowledge of physics. APS Fellows are elected on the criterion of exceptional contributions to the physics enterprise that are comprised of outstanding physics research, important applications of physics, leadership in or service to physics, or significant contributions to physics education.