Physics Colloquium: Harnessing disorder to create novel functionality in materials

The Department of Physics is pleased to welcome Dr. Nidhi Pashine for an in-person colloquium. Dr. Pashine is a Postdoctoral Researcher in Mechanical Engineering & Materials Science at Yale University. Nidhi studies granular metamaterials. Different from normal materials, these metamaterials have mechanical properties that people do not usually expect.  This presentation is part of the faculty search for an Assistant Professor of Soft Matter and/or Biological Physics.

Abstract:

Unlike crystalline solids, disordered materials live in a complex and rugged energy landscape with multiple local energy minima, each of which correspond to a different state and its own set of properties. In this multitude of possibilities, the challenge is to identify states that have interesting and desirable behavior. My work focuses on tuning elastic properties of disordered systems to create unusual mechanical behavior. For e.g., a jammed packing of granular particles has well defined bulk properties that depend on, among other factors, the interparticle interactions. Here I present “particulated” granular metamaterials – flexible tessellations filled with a small number of particles in each cell. By limiting inter-particle interactions to individual cells of a larger system, we create a material that is unlike conventional granular packings.

Another feature of disordered systems is that they are often out-of-equilibrium and evolve over time. Such a material has a memory of its history which affects its properties, including its response to external perturbations. By controlling the external forces acting on a system, we can train a material to modify and tune its elastic properties without having to control the material at the microscopic level. Disordered systems thus have the potential to be the basis for creating broad classes of materials with specific functionality.

To join the seminar remotely, please email Kevin Garvey for the Zoom information.