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arXiv · 2007.09489

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

Pedro A. Sánchez·Ekaterina V. Novak·Elena S. Pyanzina·Sofia S. Kantorovich·Joan J. Cerdà·Tomás Sintes
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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.

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Pedro A. Sánchez, Ekaterina V. Novak, Elena S. Pyanzina, Sofia S. Kantorovich, Joan J. Cerdà, Tomás Sintes. 2020-07-18. Adsorption transition of a grafted ferromagnetic filament controlled by external magnetic fields. https://doi.org/10.1103/physreve.102.022609

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