Paramagnetic colloidal ribbons in a precessing magnetic field

Abstract

We investigate the dynamics of a kink in a damped parametrically driven nonlinear Klein-Gordon equation. We show by using a method of averaging that, in the high-frequency limit, the kink moves in an effective potential and is driven by an effective constant force. We demonstrate that the shape of the solitary wave can be controlled via the frequency and the eccentricity of the modulation. This is in accordance with the experimental results reported in a recent paper [Casic et al., Phys. Rev. Lett. 110, 168302 (2013)], where the dynamic self-assembly and propulsion of a ribbon formed from paramagnetic colloids in a time-dependent magnetic field has been studied.

Contractile actuation and dynamical gel assembly of paramagnetic filaments in fast precessing fields

“…Magnetic colloids are being used for medical tasks such as drug delivery [1], tissue scaffolding [2], image contrast [3], and tumor reduction [4]. More exotic functions include self-assembling swimmers [5,6], walkers [7,8], grabbers [9], and self-healing membranes [10]. Both medical [11] and non-medical [12][13][14] applications benefit from using particles with extended aspect ratios.…”