论文标题
旋转轨道耦合抑制和旋转型库珀对旋转状态的阻塞
Spin-orbit coupling suppression and singlet-state blocking of spin-triplet Cooper pairs
论文作者
论文摘要
超导体/铁磁界面处的不均匀磁交换场将旋转的库珀对转换为自旋对准（即自旋极化）三重态。尽管对铁磁材料中此类三重态的衰减包膜进行了充分的研究，但对它们在非磁性金属和超导体中的衰变知之甚少，尤其是在旋转轨道耦合（SOC）的情况下。在这里，我们调查了将三胞胎超电流注入S波超导体NB的设备。在NB的正常状态下，三胞胎超电流在5 nm的距离上衰减，这是由于SOC与与三胞胎对相关的旋转相互作用而导致的旋转单线对衰减的数量级。在NB的超导状态下，三重式超级气流无法与单线波函数相结合，因此被单缝间隙中缺乏可用的平衡状态所阻挡。结果为S-Wave Singlet和S-Wave三胞胎状态之间的动态提供了新的见解。
An inhomogeneous magnetic exchange field at a superconductor/ferromagnet interface converts spin-singlet Cooper pairs to a spin-aligned (i.e. spin-polarized) triplet state. Although the decay envelope of such triplet pairs within ferromagnetic materials is well studied, little is known about their decay in non-magnetic metals and superconductors, and in particular in the presence of spin-orbit coupling (SOC). Here we investigate devices in which triplet supercurrents are injected into the s-wave superconductor Nb. In the normal state of Nb, triplet supercurrents decay over a distance of 5 nm, which is an order of magnitude smaller than the decay of spin singlet pairs due to the SOC interacting with the spin associated with triplet pairs. In the superconducting state of Nb, triplet supercurrents are not able to couple with the singlet wavefunction and thus blocked by the absence of available equilibrium states in the singlet gap. The results offer new insight into the dynamics between s-wave singlet and s-wave triplet states.
