Anomalous polarization-dependent transport in nanoscale double-barrier superconductor/ferromagnet/superconductor junctions
Anomalous polarization-dependent transport in nanoscale double-barrier superconductor/ferromagnet/superconductor junctions
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DOI：
10.1103/physrevb.85.180512
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发表时间：
2011-11
影响因子：
3.7
通讯作者：
Madalina Colci;K. Sun;N. Shah;S. Vishveshwara;D. Harlingen
中科院分区：
文献类型：
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作者：
Madalina Colci;K. Sun;N. Shah;S. Vishveshwara;D. Harlingen
研究了纳米尺度超导（S）器件的输运性质，其中两个超导电极由两条平行的铁磁（F）线桥接，形成一个SFFS结，两条线之间的间距小于超导相干长度。这允许发生交叉Andreev反射。我们发现，作为温度的函数的电阻表现出的行为让人想起的再入效应，并在低温和低于超导间隙的激发能量，对应于反平行排列的铁磁线的磁化强度的电阻高于平行排列，相反，从交叉Andreev反射预期的行为。我们提出了一个模型的基础上自旋相关的界面散射，解释了这一令人惊讶的结果，并展示了界面参数的结输运性质的敏感性。
We study the transport properties of nanoscale superconducting (S) devices in which two superconducting electrodes are bridged by two parallel ferromagnetic (F) wires, forming an SFFS junction with a separation between the two wires less than the superconducting coherence length. This allows crossed Andreev reflection to take place. We find that the resistance as a function of temperature exhibits behavior reminiscent of the re-entrant effect and, at low temperatures and excitation energies below the superconducting gap, the resistance corresponding to antiparallel alignment of the magnetization of the ferromagnetic wires is higher than that of parallel alignment, in contrast to the behavior expected from crossed Andreev reflection. We present a model based on spin-dependent interface scattering that explains this surprising result and demonstrates the sensitivity of the junction transport properties to interfacial parameters.