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Soliton ratchets out of point-like inhomogeneities

Luis Morales-Molina·Franz G. Mertens·Angel Sanchez
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Abstract

We introduce and study a novel design for a ratchet potential for soliton excitations. The potential is implemented by means of an array of point-like (delta) inhomogeneities in an otherwise homogeneous potential. We develop a collective coordinate theory that predicts that the effective potential acting on the soliton is periodic but asymmetric and gives rise to the ratchet effect. Numerical simulations fully confirm this prediction; quantitative agreement is reached by an improved version of the theory. Although we specifically show that it is most interesting for building Josephson junction ratchets capable to rectify time-symmetric ac forces, the proposed mechanism is very general and can appear in many contexts, including biological systems.

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Luis Morales-Molina, Franz G. Mertens, Angel Sanchez. 2003-09-08. Soliton ratchets out of point-like inhomogeneities. https://doi.org/10.1140/epjb%2Fe2004-00031-3

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