Anisotropic thermophoresis

Abstract

Colloidal migration in temperature gradient is referred to as thermophoresis. In contrast to particles with spherical shape, we show that elongated colloids may have a thermophoretic response that varies with the colloid orientation. Remarkably, this can translate into a non-vanishing thermophoretic force in the direction perpendicular to the temperature gradient. Oppositely to the friction force, the thermophoretic force of a rod oriented with the temperature gradient can be larger or smaller than when oriented perpendicular to it. The precise anisotropic thermophoretic behavior clearly depends on the colloidal rod aspect ratio, and also on its surface details, which provides an interesting tunability to the devices constructed based on this principle. By means of mesoscale hydrodynamic simulations, we characterize this effect for different types of rod-like colloids.

8 pages, 10 figures

References in corpus (7)

• Particle-Based Mesoscale Hydrodynamic Techniques
• Relevance of angular momentum conservation in mesoscale hydrodynamics simulations
• Dynamic correlations in stochastic rotation dynamics
• Direct measurement of thermophoretic forces
• Stress Tensors of Multiparticle Collision Dynamics Fluids
• Thermostat for non-equilibrium multiparticle collision dynamics simulations
• Transport coefficients of dissipative particle dynamics with finite time step

Cited by in corpus (6)

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• Dissipative particle dynamics with energy conservation: isoenergetic integration and transport properties
• Trypanosoma brucei moving in microchannels and through constrictions