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arXiv · 1012.3343

Giant transversal particle diffusion in a longitudinal magnetic ratchet

Pietro Tierno·Peter Reimann·Tom H. Johansen·Francesc Sagues
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Abstract

We study the transversal motion of paramagnetic particles on a uniaxial garnet film, exhibiting a longitudinal ratchet effect in the presence of an oscillating magnetic field. Without the field, the thermal diffusion coefficient obtained by video microscopy is $D_{0}\approx 3\times 10^{-4}$ $μm^2/s$. With the field, the transversal diffusion exhibits a giant enhancement by almost four decades and a pronounced maximum as a function of the driving frequency. We explain the experimental findings with a theoretical interpretation in terms of random disorder effects within the magnetic film.

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Pietro Tierno, Peter Reimann, Tom H. Johansen, Francesc Sagues. 2010-12-15. Giant transversal particle diffusion in a longitudinal magnetic ratchet. https://doi.org/10.1103/physrevlett.105.230602

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