Nano-dumbells pack densely to form birefringent photonic crystals

ORAL

Abstract

Monodisperse spherical colloidal particles robustly self-assemble into crystals at high concentration. We study the the self-assembly of polymer nano-dumbells and find that they crystallize only under strong confinement - in thin films less than three particles thick. On the other hand, external electric fields can readily align dumbbell- shaped particles to make a birefringent suspension. When the electric field is turned off, the dumbbells rapidly lose their orientational order and the birefringence quickly goes away. However, if the solvent is removed with the electric field on, the particles self-assemble into a novel dense crystalline packing hundreds of particles thick. We describe the essential physics of self-assembly of these structures through an interplay of the applied electric field and capillary forces.

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Authors

  • Jason Forster

    • Yale

  • Jin-Gyu Park

    • Yale

  • Manish Mittal

    • University of Delaware

  • Vinodkumar Saranathan

    • Yale

  • Heeso Noh

    • Yale

  • Carl Schreck

    • Departments of Chemical Engineering, Physics, Mechanical Engineering and Materials Science, and Molecular Biophysics and Biochemistry, Yale University
    • Department of Physics
    • Yale University
    • Yale

  • Richard Prum

    • Yale

  • Corey O'Hern

    • Yale University
    • Departments of Chemical Engineering, Physics, Mechanical Engineering and Materials Science, and Molecular Biophysics and Biochemistry, Yale University
    • Yale

  • Hui Cao

    • Yale University, Departments of Physics and Applied Physics
    • Yale

  • Eric Furst

    • University of Delaware

  • Eric Dufresne

    • Yale University, Departments of Mechanical Engineering, Physics, Chemical Engineering, and Cell Biology
    • Yale University
    • Yale