Instability caused swimming of ferromagnetic filaments in pulsed field

Abstract

Magnetic filaments driven by external magnetic field are an interesting topic of research in-terms of the possible bio-medical applications. In this paper, we investigated the applicability of using ferromagnetic filaments as micro swimmers both experimentally and numerically. It was found that applying a pulse wave field profile with a duty cycle of 30$$\%$$ % induced experimentally observable swimming, which is similar to the breast stroke of micro algae. Good agreement with numerical simulations was found. Moreover, for stable continuous swimming, an initial filament shape is required to avoid transition to the structurally preferred non-swimming S-like mode.

Dynamic magnetic properties of magnetosomes

“…The predicted high-frequency behaviour was tested in experiments on magnetosomes, and the results were consistent with the theory, at least over two decades in frequency [39]. The nonlinear dynamics of magnetic filaments in AC magnetic fields have been shown to lead to a wide range of unusual phenomena [40] including alignment perpendicular to the field [41], oscillating S-, U-, and Z-shaped configurations [41,42], fourarched configurations [42], buckling [43], and microswimming behaviour [44].…”