Stewart McWilliams

Research

I study high pressure and high temperature states of matter in the laboratory to address questions of natural and technological interest.  I am interested in materials relevant to natural systems such as planetary interiors and to technologies such as energetic materials and inertial confinement fusion.  


I develop ultrafast methods to create, sustain, and study extreme states. Primarily I use the diamond-anvil cell (static compression) and laser-driven shock waves (dynamic compression) to generate extreme conditions in microscale samples.  I visit facilities worldwide for access to high power laser systems and brilliant x-ray radiation in order to create and probe these states.


I primarily study the fundamental properties of materials under extreme pressure and temperature, and how these change as conditions become more extreme. These include strength, elastic moduli, optical properties, electronic properties, transport behavior (e.g. thermal conductivity and viscosity), phase diagrams including melting, and crystal and liquid structures.


Wherever possible, I examine how these findings can inform our understanding of natural systems where extreme pressures and temperatures are commonplace, such as in the interiors of the Earth, other terrestrial planets, giant planets and extrasolar planets.  I also examine how extreme conditions can be used to synthesize new materials.



European XFEL 2019

Community Proposal #2292

European XFEL

JANUS

Lawrence Livermore National Laboratory