Adsorption transition of a grafted ferromagnetic filament controlled by external magnetic fields

TL;DR

This study uses Langevin dynamics simulations to explore how external magnetic fields influence the adsorption transition of a grafted ferromagnetic filament, revealing controllable switching mechanisms and structural transitions.

Contribution

It introduces a detailed simulation analysis of magnetic filament adsorption, highlighting the effects of magnetic fields on adsorption behavior and structural transitions.

Findings

Magnetic filaments have higher adsorption temperatures than nonmagnetic chains.

External magnetic fields can precisely control the adsorption process.

A power law relates the field strength and tilt angle at adsorption.

Abstract

Extensive Langevin dynamics simulations are used to characterize the adsorption transition of a flexible magnetic filament grafted onto an attractive planar surface. Our results identify different structural transitions at different ratios of the thermal energy to the surface attraction strength: filament straightening, adsorption and the magnetic flux closure. The adsorption temperature of a magnetic filament is found to be higher in comparison to an equivalent nonmagnetic chain. The adsorption has been also investigated under the application of a static homogeneous external magnetic field. We found that the strength and the orientation of the field can be used to control the adsorption process, providing a precise switching mechanism. Interestingly, we have observed that the characteristic field strength and tilt angle at the adsorption point are related by a simple power law.