Rusanov A Yu, Hesselberth M, Aarts J, Buzdin A I
Kamerlingh Onnes Laboratory, Universiteit Leiden, P.O. Box 9504, 2300 RA Leiden, The Netherlands.
Phys Rev Lett. 2004 Jul 30;93(5):057002. doi: 10.1103/PhysRevLett.93.057002.
In (S/F) hybrids the suppression of superconductivity by the exchange field h(ex) of the ferromagnet can be partially lifted when different directions of h(ex) are sampled simultaneously by the Cooper pair. In F/S/F trilayers where the magnetization directions of the F layers can be controlled separately, this leads to the so-called spin switch. Here we show that domain walls in a single F layer yield a similar effect. We study the transport properties of Ni(0.80)Fe(0.20)/Nb bilayers structured in strips of different sizes. For large samples a clear enhancement of superconductivity takes place in the resistive transition, in the very narrow field range (order of 0.5 mT) where the magnetization of the Py layer switches and many domains are present. This effect is absent in microstructured samples.
在（S/F）混合体系中，当库珀对同时探测到铁磁体的交换场h(ex)的不同方向时，铁磁体的交换场h(ex)对超导性的抑制作用可以部分解除。在F/S/F三层结构中，其中F层的磁化方向可以分别控制，这会导致所谓的自旋开关效应。在这里，我们表明单个F层中的畴壁会产生类似的效果。我们研究了不同尺寸条带状结构的Ni(0.80)Fe(0.20)/Nb双层膜的输运性质。对于大尺寸样品，在Py层磁化翻转且存在许多畴的非常窄的场范围（约0.5 mT）内，电阻转变中会出现明显的超导增强。这种效应在微结构样品中不存在。
