de Souza Silva C C, Silhanek A V, Van de Vondel J, Gillijns W, Metlushko V, Ilic B, Moshchalkov V V
INPAC-Institue for Nanoscale Physics and Chemistry, Nanoscale Superconductivity and Magnetism and Pulsed Fields Group, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, B-3001 Leuven, Belgium.
Phys Rev Lett. 2007 Mar 16;98(11):117005. doi: 10.1103/PhysRevLett.98.117005. Epub 2007 Mar 15.
We investigate the transport properties of superconducting films with periodic arrays of in-plane magnetized micromagnets. Two different magnetic textures are studied: a square array of magnetic bars and a close-packed array of triangular microrings. As confirmed by magnetic force microscopy imaging, the magnetic state of both systems can be adjusted to produce arrays of almost pointlike magnetic dipoles. By carrying out transport measurements with ac drive, we observed experimentally a recently predicted ratchet effect induced by the interaction between superconducting vortices and the magnetic dipoles. Moreover, we find that these magnetic textures produce vortex-antivortex patterns, which have a crucial role in the transport properties of this hybrid system.
我们研究了具有面内磁化微磁体周期性阵列的超导薄膜的输运性质。研究了两种不同的磁结构：磁棒的方形阵列和紧密排列的三角形微环阵列。通过磁力显微镜成像证实，这两个系统的磁状态都可以调整，以产生几乎点状磁偶极子的阵列。通过进行交流驱动的输运测量，我们通过实验观察到了最近预测的由超导涡旋与磁偶极子之间的相互作用引起的棘轮效应。此外，我们发现这些磁结构产生了涡旋-反涡旋图案，这在这种混合系统的输运性质中起着关键作用。
