Spin current in junctions composed of multi-band superconductors with a spin-density wave
Spin current in junctions composed of multi-band superconductors with a spin-density wave
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DOI：
10.1088/0953-2048/28/2/025011
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发表时间：
2015-01
影响因子：
3.6
通讯作者：
A. Moor;A. Volkov;K. Efetov
中科院分区：
文献类型：
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作者：
A. Moor;A. Volkov;K. Efetov
我们计算了一个非耗散的自旋电流，并证明它可以在有或没有电荷电流的情况下流动。我们考虑了一种双波段模型，该模型可用于描述超导和自旋密度波共存状态下的铁基化合物。利用准经典格林函数方法和隧道哈密顿方法，我们证明了在保持自旋电流有限的情况下存在关闭约瑟夫森电流的可能性。此外，可以使临界约瑟夫森电流和临界自旋电流成正比，从而提供了通过约瑟夫森电流测量自旋电流的可能性。其基本机制是组成结的超导体不同带间电子空穴对的干扰跳变。这是该系统的固有特性，并提供了一种独特而自然的方法，可以在自旋电子学器件中有前途的应用中利用完全由聚合物制成的结。
We calculate a nondissipative spin current and show that it can flow with or without a charge current. We consider a two-band model which can be applied to the description of Fe-based pnictides in coexistence regime of superconductivity and spin-density wave. Using quasiclassical Greenʼs functions approach and tunneling Hamiltonian method we show that there exists a possibility to switch off the Josephson current while leaving the spin current finite. Moreover, it is possible to have the critical Josephson current and the critical spin current being proportional to each other, thus giving a possibility to measure the spin current via the Josephson current. The underlying mechanism is the interfering hopping of electron–hole pairs between different bands of the superconductors composing the junction. This is an intrinsic property of the system and provides a unique and natural way to utilize junctions made solely of pnictides in promising applications in spintronics devices.