Regensburg 2019 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

DY: Fachverband Dynamik und Statistische Physik

DY 43: Anomalous diffusion / Brownian motion

DY 43.8: Vortrag

Donnerstag, 4. April 2019, 12:00–12:15, H3

Long-time tails of correlation functions of Brownian particlesSuvendu Mandal1, •Lukas Schrack2, Hartmut Löwen1, Matthias Sperl3, and Thomas Franosch21Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany — 2Institut für Theoretische Physik, Leopold-Franzens-Universität, Technikerstraße 21A, 6020 Innsbruck, Austria — 3Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt, Linder Höhe, 51147 Köln, Germany

The dynamics of Brownian particles of a hard-sphere fluid can be described by generalized Langevin equations. Starting with the microscopic motion of the colloids we use the Zwanzig-Mori projection operator formalism to derive equations of motion for correlation functions. To close the equations, suitable mode-coupling approximations (slowing down of the dynamics due to the caging by neighboring particles) are used. Introducing a logarithmically spaced wavevector grid we investigate the long-wavelength behavior of the system. The velocity autocorrelation function of a tagged particle decays algebraically as ∝ t−5/2 rather than exponentially due to repeated interactions. Comparing the collective dynamics with the self-dynamics for different packing fractions near the glass transition we find that contrary to the self-dynamics the collective dynamics do not slow down.

100% | Mobil-Ansicht | English Version | Kontakt/Impressum/Datenschutz
DPG-Physik > DPG-Verhandlungen > 2019 > Regensburg