Regensburg 2010 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
DY: Fachverband Dynamik und Statistische Physik
DY 6: Poster Session I
DY 6.52: Poster
Montag, 22. März 2010, 16:00–18:00, Poster B2
Field-induced ordering, non-local susceptibilities and non-affine noise in 2D colloidal crystals — •Kerstin Franzrahe1, Surajit Sengupta2, and Peter Nielaba1 — 1Department of Physics, University of Konstanz, Germany — 2CAM, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, India
Ordering phenomena in monolayers interacting with a substrate are studied by MC-simulations of binary hard-disk mixtures. Here the influence of a substrate is modelled by a 1D spatially periodic external potential. For the field-free case the thermodynamic stability of space-filling lattice structures for such mixtures is analysed[1]. As these structures are stable only in high pressure environments, the phase behaviour of a binary 50% mixture with a diameter ratio σB/σA=0.414 exposed to a substrate potential is studied in detail[1-3].
Furthermore our focus is on the elasticity of 2D soft matter systems. Using a coarse graining procedure the local strain fields and hence the elastic moduli can be computed from the local displacement fields. We show that for a triangular, harmonic lattice coarse graining local strains obtained from MC-simulations generates non-trivial, non-local strain correlations. These may be understood within a generalised, Landau type elastic Hamiltonian[2,4]. Apart from the smooth, affine strain fields, this procedure also gives rise to a noise field made up of non-affine displacements. [1] K. Franzrahe, P. Nielaba, Phys. Rev. E 79, 051505, (2009); [2] K. Franzrahe et al., J. Phys.: Cond. Mat. 20, 404218, (2008); [3] K. Franzrahe, P. Nielaba, Phys. Rev. E 76, 061503, (2007); [4] K. Franzrahe et al., Phys. Rev. E 78, 026106, (2008).