Events

  • Physics and Astronomy Postponed Exams

    DRL, Room A4

     

     

  • Department Colloquium: TBD

    A8

    James Aguirre, UPenn

  • Condensed Matter Seminar: "Shaping Colloidal Assembly"

    A4

    Professor Greg van Anders, University of Michigan

    Advances in synthesis techniques have produced colloids and nanoparticles in a diverse array of shapes that can be assembled into bulk structures. That bulk structure is strongly affected by particle shape in idealized systems is widely established in the literature. However, this literature leaves open three key questions: (i) We know that shape affects structure, but how? (ii) Does shape continue to matter in experimental systems where other interactions are present? (iii) How do we tailor colloid shape for a target structure?
  • Condensed Matter Seminar: Toroidal droplets – Breakup, Stabilization and Nematic order

    A4

    Professor, Alberto Fernandez-Nieves, Georgia Tech

    In this talk, we will discuss the generation of toroidal droplets and their stabilization against surface-tension-driven instabilities using yield stress materials. We will then discuss what happens when the drops are made out of nematic liquid crystal. In this case, when the anchoring is planar degenerate, we find that the director spontaneously twists and that the twisted structure remains irrespective of how thin or fat the tori are. Our interpretation is that this results from saddle-splay contributions to the Frank free energy of the system.

  • Condensed Matter Seminar: "Building Colloidal Aggregates in Anisotropic Media"

    A4

    Professor Colin Denniston, Western Ontario University

    Colloids in a liquid crystal matrix exhibit very anisotropic interactions. Further, these interactions can be altered by both properties of the colloid and of the liquid crystal. This gives the potential for creating specific colloidal aggregates and crystals by manipulating the interactions between colloids using the colloidal shape, surface properties, and even dynamics. However, modelling these interacting colloids in a liquid crystal is very challenging.

  • Department Colloquium: TBD

    A8

    Adam Lidz, UPenn

  • Condensed Matter Seminar: “Making Cells with Active Micro-tubule Mixtures”

    A4

    Professor Jennifer Ross, UMass Amherst

    Biology utilizes energy to organize itself from the nanoscale to the macroscopic scale. We seek to determine the universal principles of organization from the molecular scale that gives rise to architecture on the cellular scale. We are specifically interested in the organization of the microtubule cytoskeleton, a rigid, yet versatile network in most cell types. Microtubules in the cell are organized by motor proteins and crosslinkers.

  • Department Colloquium: TBD

    A8

    Douglas Stone, Yale

  • Condensed Matter Seminar: Microfluidic Pathways towards Topological Defect Templates

    A4

    Professor Anupam Sengupta, MIT

    Liquid crystals (LCs) are mesogenic phases of matter which combine liquid fluidity with crystalline solid properties.The material anisotropy allows us to explore LCs as complex functional materials for microfluidics. Harnessing the anisotropic coupling between the flow and the molecular ordering renders a novel perspective to the conventional concepts in microfluidics.

  • Condensed Matter Seminar: Design of Biotic-Abiotic Interfaces using Liquid Crystals

    A4

    Professor Nicholas Abbott, University of Wisconsin

    Many biological molecules form liquid crystalline phases.  The unique combination of long-range molecular ordering and mobility found in liquid crystals has been exploited by nature to create a range of functional and living systems.  We are pursuing studies that seek to create synthetic liquid crystalline materials that recapitulate biological design principles and can be used to couple biotic and abiotic systems in useful ways.