2005/04/17 by Peter Lipowsky, Mark J. Bowick, Jan H. Meinke +2
Materials Science · Physics and Astronomy · #Material Dynamics and Properties #Microstructure and mechanical properties #Pickering emulsions and particle stabilization #cond-mat.mtrl-sci #cond-mat.soft
paper · pdf · doi:10.1038/nmat1376
published as Nat. Mat. 4 (2005) 407 · 11 pages, 4 figures, pdf format
openalex publication_date 2005/04/17 · arxiv created 2005/06/15 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Mesoscale objects with unusual structural features may serve as the analogues of atoms in the design of larger-scale materials with novel optical, electronic or mechanical behaviour. In this paper we investigate the structural features and the equilibrium dynamics of micron-scale spherical crystals formed by polystyrene particles adsorbed on the surface of a spherical water droplet. The ground state of sufficiently large crystals possesses finite-length grain boundaries (scars). We determine the elastic response of the crystal by measuring single-particle diffusion and quantify the fluctuations of individual dislocations about their equilibrium positions within a scar determining the dislocation spring constants. We observe rapid dislocation glide with fluctuations over the barriers separating one local Peierls minimum from the next and rather weak binding of dislocations to their associated scars. The long-distance (renormalised) dislocation diffusion glide constant is extracted directly from the experimental data and is found to be moderately faster than single particle diffusion. We are also able to determine the parameters of the Peierls potential induced by the underlying crystalline lattice.