The chiral magnetic nanomotors

Abstract

Propulsion of the chiral magnetic nanomotors powered by a rotating magnetic field is in the focus of the modern biomedical applications. This technology relies on strong interaction of dynamic and magnetic degrees of freedom of the system. Here we study in detail various experimentally observed regimes of the helical nanomotor orientation and propulsion depending on the actuation frequency, and establish the relation of these two properties with remanent magnetization and geometry of the helical nanomotors. The theoretical predictions for the transition between the regimes and nanomotor orientation and propulsion speed are in excellent agreement with available experimental data. The proposed theory offers a few simple guidelines towards the optimal design of the magnetic nanomotors. In particular, efficient nanomotors should be fabricated of hard magnetics, e.g., cobalt, magnetized transversally and have the geometry of a normal helix with a helical angle of 35-45 degrees.

Submitted to Nano Letters on July 12, 2013

References in corpus (2)

• Enhanced low-Reynolds-number propulsion in heterogeneous viscous environments
• Dynamical Configurations and Bistability of Helical Nanostructures under External Torque

Cited by in corpus (7)

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• Dynamics and polarization of superparamagnetic chiral nanomotors in a rotating magnetic field
• The role of symmetry in driven propulsion at low Reynolds number
• Using Shape Diversity on the way to new Structure-Function Designs for Magnetic Micropropellers
• Hydrodynamic Interactions between Two Forced Objects of Arbitrary Shape: I Effect on Alignment
• Weak thermal fluctuations impede steering of chiral magnetic nanobots
• Spatial dynamics of flexible nano-swimmers under a rotating magnetic field