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Updated: Jun 29, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Dynamical density functional theory with hydrodynamic interactions and colloids in unstable traps
1Institut für Theoretische Physik II: Weiche Materie, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany. rexm@thphy.uni-duesseldorf.de
Abstract:
A density functional theory for colloidal dynamics is presented which includes hydrodynamic interactions between the colloidal particles. The theory is applied to the dynamics of colloidal particles in an optical trap which switches periodically in time from a stable to an unstable confining potential. In the absence of hydrodynamic interactions, the resulting density breathing mode exhibits huge single peaked oscillations in the trap center which become double peaked and damped by hydrodynamic interactions. The predicted dynamical density fields are in good agreement with Brownian dynamics computer simulations.
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