Steady states of non-axial dipolar rods driven by rotating fields
SOFT MATTER, 16 (5):
1201-1210 (2020)DOI: 10.1039/c9sm01671f
Abstract
We investigate a two-dimensional system of magnetic colloids with
anisotropic geometry (rods) subjected to an oscillating external
magnetic field. The structural and dynamical properties of the steady
states are analyzed, by means of Langevin dynamics simulations, as a
function of the misalignment of the intrinsic magnetic dipole moment of
the rods with respect to their axial direction, and also in terms of the
strength and rotation frequency of an external magnetic field. The
misalignment of the dipole relative to their axial direction is inspired
by recent studies, and this is extremely relevant in the microscopic
aggregation states of the system. The dynamical response of the magnetic
rods to the external magnetic field is strongly affected by such a
misalignment. Concerning the synchronization between the magnetic rods
and the direction of the external magnetic field, we define three
distinct regimes of synchronization. A set of steady states diagrams are
presented, showing the magnitude and rotation frequency intervals in
which the distinct self-organized structures are observed.