Symmetries of Pairing Correlations in Superconductor–Ferromagnet Nanostructures
Symmetries of Pairing Correlations in Superconductor–Ferromagnet Nanostructures
复制标题
超导体-铁磁体纳米结构中配对相关性的对称性
DOI：
10.1007/s10909-007-9329-6
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发表时间：
2006
影响因子：
2
通讯作者：
G. Schön
中科院分区：
文献类型：
--
作者：
M. Eschrig;T. Löfwander;T. Champel;J. Cuevas;J. Kopu;G. Schön
使用泡利原理施加的选择规则，我们根据配对相关性在自旋、动量和能量方面的对称性对配对相关性进行分类。我们观察到，不均匀性总是导致偶数和奇数能量配对分量的混合。我们研究了超导体和铁磁体之间界面附近存在的超导配对相关性，重点关注由单线态超导体和弱或半金属铁磁体组成的清洁系统。界面区域中的自旋主动散射引起所有可能的对称分量。特别是，长程等自旋配对相关性具有可比较幅度的奇数频率 s 波和偶数频率 p 波分量。我们还分析了通过半金属的约瑟夫森电流。我们发现了隧道极限内临界电流的温度依赖性的解析表达式和普遍性。
Using selection rules imposed by the Pauli principle, we classify pairing correlations according to their symmetry properties with respect to spin, momentum, and energy. We observe that inhomogeneity always leads to mixing of even- and odd-energy pairing components. We investigate the superconducting pairing correlations present near interfaces between superconductors and ferromagnets, with focus on clean systems consisting of singlet superconductors and either weak or half-metallic ferromagnets. Spin-active scattering in the interface region induces all of the possible symmetry components. In particular, the long-range equal-spin pairing correlations have odd-frequency s-wave and even-frequency p-wave components of comparable magnitudes. We also analyze the Josephson current through a half-metal. We find analytic expressions and a universality in the temperature dependence of the critical current in the tunneling limit.