Topologically protected colloidal transport above a square magnetic lattice

TL;DR

This paper demonstrates theoretically and through simulations that magnetic colloidal particles can be robustly transported across a patterned magnetic surface using topologically protected magnetic field loops, ensuring stable movement despite perturbations.

Contribution

It introduces the concept of topologically protected colloidal transport driven by magnetic field modulation over a square magnetic lattice, combining theory and simulations.

Findings

Transport is robust against perturbations.

Topologically protected transport occurs between different unit cells.

Theory and simulations show perfect agreement.

Abstract

We theoretically study the motion of magnetic colloidal particles above a magnetic pattern and compare the predictions with Brownian dynamics simulations. The pattern consists of alternating square domains of positive and negative magnetization. The colloidal motion is driven by periodic modulation loops of an external magnetic field. There exist loops that induce topologically protected colloidal transport between two different unit cells of the pattern. The transport is very robust against internal and external perturbations. Theory and simulations are in perfect agreement.