Enhanced diffusion and anomalous transport of magnetic colloids driven above a two-state flashing potential

Abstract

We combine experiment and theory to investigate the diffusive and subdiffusive dynamics of paramagnetic colloids driven above a two-state flashing potential. The magnetic potential was realized by periodically modulating the stray field of a magnetic bubble lattice in a uniaxial ferrite garnet film. At large amplitudes of the driving field, the dynamics of particles resembles an ordinary random walk with a frequency-dependent diffusion coefficient. However, subdiffusive and oscillatory dynamics at short time scales is observed when decreasing the amplitude. We present a persistent random walk model to elucidate the underlying mechanism of motion, and perform numerical simulations to demonstrate that the anomalous motion originates from the dynamic disorder in the structure of the magnetic lattice, induced by slightly irregular shape of bubbles.

arXiv comment9 pages, 8 figures

References in corpus (17)

• Brownian motors: noisy transport far from equilibrium
• Self-motile colloidal particles: from directed propulsion to random walk
• Artificial Brownian motors: Controlling transport on the nanoscale
• Diffusion on a solid surface: Anomalous is normal
• Vortex rectification effects in films with periodic asymmetric pinning
• Self-propelled particles with fluctuating speed and direction of motion
• Ratchet-like dynamics of fluxons in annular Josephson junctions driven by bi-harmonic microwave fields
• Feedback control in a collective flashing ratchet
• Quantum ratchet effect for vortices
• Dynamics, Rectification, and Fractionalization for Colloids on Flashing Substrates
• Anomalous Diffusion of Self-Propelled Particles in Directed Random Environments
• Density-dependent diffusion in the periodic Lorentz gas
• Persistent-random-walk approach to anomalous transport of self-propelled particles
• Excluded volume causes integer and fractional plateaus in colloidal ratchet currents
• Diffusive transport of light in a two-dimensional disordered packing of disks: Analytical approach to transport-mean-free path
• Fast and rewritable colloidal assembly via field synchronized particle swapping
• Diffusive transport of light in two-dimensional granular materials

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