论文标题
二维磁性约瑟夫森连接中的子仪模式
Subgap modes in two-dimensional magnetic Josephson junctions
论文作者
论文摘要
我们考虑二维超导体/铁磁性/超导体连接器，并沿交界接口进行了子段模式。子仪模式表现出类似于Yu-Shiba-Rusinov的特征，这些特征起源于磁连接处的超导性与铁磁磁性之间的相互作用。子仪模式的分散关系根据铁磁铁的运输状态（金属，半金属或绝缘）显示在质量上不同的曲线。随着铁磁体中的自旋分裂的增加，子段模式在整个交界处的约瑟夫森电流中带来了约$ 0 $ - $π$的过渡，而约瑟夫森电流密度取决于沿着连接接口的动量（即事件电流的方向）。对于清洁的超导体 - 铁磁性界面（即超导体和铁磁铁之间的强耦合），子段模式会形成平坦的准粒子频带，从而使沿着不均匀的磁性交界处允许沿着不均匀的磁性连接来设计subgap模式的波浪函数。
We consider two-dimensional superconductor/ferromagnet/superconductor junctions and investigate the subgap modes along the junction interface. The subgap modes exhibit characteristics similar to the Yu-Shiba-Rusinov states that originate form the interplay between superconductivity and ferromagnetism in the magnetic junction. The dispersion relation of the subgap modes shows qualitatively different profiles depending on the transport state (metallic, half-metallic, or insulating) of the ferromagnet. As the spin splitting in the ferromagnet is increased, the subgap modes bring about a $0$-$π$ transition in the Josephson current across the junction, with the Josephson current density depending strongly on the momentum along the junction interface (i.e., the direction of the incident current). For clean superconductor-ferromagnet interfaces (i.e., strong coupling between superconductors and ferromagnet), the subgap modes develop flat quasi-particle bands that allow to engineer the wave functions of the subgap modes along an inhomogeneous magnetic junction.
