Colloidal Model for Investigating Optimal Efficiency in Weakly Coupled Ratchet Motors

Abstract

We investigate the transport of superparamagnetic colloidal particles along self-assembled tracks using a periodically applied magnetic field as a model for ratchetlike mechanisms. Through video microscopy and simulations, we examine how different factors influence transport efficiency. The findings reveal that processive motion can be achieved without residual attraction, with optimal transport efficiency governed by the combined effects of particle size ratios, actuation frequency, track roughness, and asymmetry in the applied potential. Additionally, we explore alternative strategies, including weak residual attraction and alternating magnetic fields, to further enhance efficiency. These findings provide valuable insights for the development of synthetic micro- and nanomotors with potential applications in drug delivery and environmental remediation.