Our group studies the dynamics of rapid transformations in materials, at the nanoscale and molecular scale. We are particularly interested in the initial stages of nonequilibrium phase transitions in metastable liquids.
We prepare microscale and nanoscale liquid systems which undergo ultrafast transformations occuring in millionths or billionths of a second. To study these tranformations, we use optical and X-ray techniques that have very high temporal resolution, down to the femtosecond regime.
Most of our studies are based on cutting-edge experiments we conduct at X-ray laser facilities, which allow us to observe the dynamics of transformations at ultrafast time scales. We also use the X-ray lasers to generate nonequilibrium conditions and induce very rapidly phase changes such as cavitation, or to generate microscale shock waves and study their behavior.
Experiements at X-ray laser facilities explore new physical regimes and uncover new physics, which often require developing new types of data analysis and modeling tools. A significant part of our recent work consists of developing new models and modeling tools motivated by our experiments, such as developing stochastic models of the freezing of supercooled water drops, and high-fidelity ray-tracing image simulations.