Realization of the Najafi-Golestanian microswimmer

TL;DR

This paper reports the experimental realization of a three-linked-spheres microswimmer powered by a magnetic field, supported by a harmonic oscillator model, demonstrating a versatile approach for designing efficient microswimmers.

Contribution

It introduces an experimental implementation of the Najafi-Golestanian microswimmer using self-assembled ferromagnetic particles and a magnetic field, along with a general harmonic oscillator model.

Findings

Successful creation of a microswimmer at an air-water interface.

Model accurately reproduces experimental behavior.

Potential for designing various efficient microswimmers.

Abstract

A paradigmatic microswimmer is the three-linked-spheres model, which follows a minimalist approach for propulsion by shape shifting. As such, it has been the subject of numerous analytical and numerical studies. In this Rapid Communication, an experimental three-linked-spheres swimmer is created by self-assembling ferromagnetic particles at an air-water interface. It is powered by a uniform oscillating magnetic field. A model, using two harmonic oscillators, reproduces the experimental findings. Because the model remains general, the same approach could be used to design a variety of efficient microswimmers.