Shear-Induced Dynamic Polarization and Mesoscopic Structure in Suspensions of Polar Nanorods

Institut für Theoretische Physik, Technische Universität Berlin, Hardenbergstrasse 36, D-10623 Berlin, Germany.
Physical Review Letters (Impact Factor: 7.51). 02/2009; 102(2):028301. DOI: 10.1103/PhysRevLett.102.028301
Source: PubMed


We investigate the spatiotemporal behavior of sheared suspensions of rodlike particles with permanent dipole moments. Our calculations are based on a self-consistent hydrodynamic model including feedback effects between orientational motion and velocity profile. The competition between shear-induced tumbling motion and the boundary conditions imposed by plates leads to oscillatory alignment structures. These give rise to a spontaneous time-dependent polarization generating, in turn, magnetic fields. This novel shear-induced effect is robust against varying the boundary conditions. The field strengths are of a measurable magnitude for a broad parameter range.

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