Watching the dynamics of phase transitions from atomic to nanoscopic length scales

Abstract:

Phase transitions result in large, macroscopic changes in material properties and increasingly technology is turning to exploit these changes to power the next generation devices. However, thermally driven phase transitions are often heterogeneous; we often see water existing simultaneously in the liquid and solid state when ice melts. It is important to understand this heterogeneity when trying to understand the properties of materials during switching. However, it is less clear how or if heterogeneity manifests itself when phase transitions occur on an ultrafast timescale drive by light or how even to observe it on these short time and length scales.
In this talk, I will discuss how X-Ray free electron lasers allow us to image the measure the impact of heterogeneity in ultrafast phase transitions and how we can exploit this information for ultrafast material control.