Transverse ratchet effect and superconducting vortices: simulation and experiment

A transverse ratchet effect has been measured in magnetic/ superconducting hybrid films fabricated by electron beam lithography and magnetron sputtering techniques. The samples are Nb films grown on top of an array of Ni nanotriangles. Injecting an ac current parallel to the triangle reflection symmetry axis yields an output dc voltage perpendicular to the current, due to a net motion of flux vortices in the superconductor. The effect is reproduced by numerical simulations of vortices as Langevin particles with realistic parameters. Simulations provide an intuitive picture of the ratchet mechanism, revealing the fundamental role played by the random intrinsic pinning of the superconductor

Transverse ratchet effect and superconducting vortices: simulation and experiment

A transverse ratchet effect has been measured in magnetic/superconducting hybrid films fabricated by electron beam lithography and magnetron sputtering techniques. The samples are Nb films grown on top of an array of Ni nanotriangles. Injecting an ac current parallel to the triangle reflection symmetry axis yields an output dc voltage perpendicular to the current, due to a net motion of flux vortices in the superconductor. The effect is reproduced by numerical simulations of vortices as Langevin particles with realistic parameters. Simulations provide an intuitive picture of the ratchet mechanism, revealing the fundamental role played by the random intrinsic pinning of the superconductor.We acknowledge funding support by Spanish Ministerio de Ciencia e Innovación grants NAN04-09087 and MOSAICO, FIS2005-07392 Consolider CSD2007-00010, FIS2008-06249 (Grupo Consolidado) and CAM grant S-0505/ESP/0337 and Fondo Social Europeo. Computer simulations of this work were performed at the "Cluster de cálculo para Técnicas Físicas" at UCM, funded in part by UE-FEDER program and in part by UCM.Peer reviewe