Structure Formation and Deformation Dynamics in Hard-Sphere Colloidal Materials

Tuesday, March 12, 2013 – 11:00am
Regents 351
Katharine Jensen
Harvard University

Understanding how atomic-scale structures and dynamics give rise to the macroscopic properties of materials can be very difficult. In an ideal experiment, we would simply observe the three dimensional trajectories of every atom in the material over time and link these local motions to the bulk properties. Unfortunately, atoms are too small and move too quickly to do this. However, by using colloids consisting of micrometer-scale solid particles surrounded by a fluid as scale models of atomic crystals and glasses, we are able to use confocal microscopy to perform this ideal experiment. I will discuss the physics of forming crystals and glasses from simple, hard-sphere colloidal particles and how we’ve used these colloids to investigate the structure, defects, and dynamics of crystalline and amorphous materials, with particular focus on the mechanisms of deformation in glasses.

Host: Daniel Blair