Berlin 2008 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

DY: Fachverband Dynamik und Statistische Physik

DY 17: Poster I

DY 17.48: Poster

Dienstag, 26. Februar 2008, 16:00–18:00, Poster C

On multiplicative forcing effects in the Cahn-Hilliard model — •Christian Feller, Alexei Krekhov, and Walter Zimmermann — Theoretische Physik I, Universität Bayreuth, 95440 Bayreuth, Germany

Phase separation in the presence of spatially periodic temperature modulation has been investigated theoretically in terms of a generalized Cahn-Hilliard model, where the temperature modulation is described by a spatially periodic modulation G cos(Qx) of the control parameter.
One obtains for harmonic and subharmonic solutions with respect to the modulation of the control parameter different thresholds for the bifurcation from the basic state. The threshold for the harmonic solutions is always lower. Beyond the threshold there exists a discrete set of periodic solutions characterized by the wave number Q/m (with integer m) which become stable only beyond a certain second threshold. In the nonlinear regime numerical simulations of the phase separation dynamics in one and two dimensions are compared with the results of linear stability analysis.