Description:

Abstract: When a disordered jammed solid is sheared for many cycles at constant strain amplitude, it can relax until the same particle rearrangements repeat in each cycle. I present two ways this simple kind of mechanical annealing helps illuminate these materials’ complexity. First, experiments with a 2D colloidal solid show that annealing gives the material the ability to remember the amplitudes of deformations, in a way that seemingly defies its glassy, frustrated nature. Second, I discuss possible signatures of the material’s glassy physics that cannot be annealed away: orbits in which the period of particle motions is a multiple of the period of driving, and a peculiar enhancement of memory capacity. These results highlight the value of memory as a perspective on non-equilibrium matter.

Speaker: Nathan Keim, Associate Research Professor, Penn State University 

Host: Professor Michelle Driscoll

https://northwestern.zoom.us/j/98500657901?pwd=OGRsTk9XamxJSU5SaG9jdnkwUFM4Zz09

Meeting ID: 985 0065 7901 
Passcode: 479321