论文标题
Yu-Shiba-Rusinov态和超导纳米线边界附近的磁杂质的订购
Yu-Shiba-Rusinov States and Ordering of Magnetic Impurities Near the Boundary of a Superconducting Nanowire
论文作者
论文摘要
从理论上讲，我们在一维纳米线的边界附近通过一个和两个磁杂质引起的光谱，靠近常规的$ s $波超导体，并提取基态磁性构型。我们表明，由磁性杂质支持的子段状态的能量受到边界的强烈影响，距离小于超导相干长度。特别是，当杂质向边界移动时，定期发生多个量子相变，其中超导冷凝水的均衡性在均匀和奇数之间振荡。我们发现，两个磁杂质的磁接地状态构型不仅取决于它们之间的距离，而且还取决于它们距离纳米线边界的距离。结果，磁接地状态可以从铁磁变为防铁磁磁性，同时保持障碍之间的距离，而同时将两个杂质从边界移开。在弱耦合方案中分析发现了两种杂质的基态磁构型，并且完全用于使用数值紧密结合模拟的任意杂质耦合强度。
We theoretically study the spectrum induced by one and two magnetic impurities near the boundary of a one-dimensional nanowire in proximity to a conventional $s$-wave superconductor and extract the ground state magnetic configuration. We show that the energies of the subgap states, supported by the magnetic impurities, are strongly affected by the boundary for distances less than the superconducting coherence length. In particular, when the impurity is moved towards the boundary, multiple quantum phase transitions periodically occur in which the parity of the superconducting condensate oscillates between even and odd. We find that the magnetic ground state configuration of two magnetic impurities depends not only on the distance between them but also explicitly on their distance away from the boundary of the nanowire. As a consequence, the magnetic ground state can switch from ferromagnetic to antiferromagnetic while keeping the inter-impurity distance unaltered by simultaneously moving both impurities away from the boundary. The ground state magnetic configuration of two impurities is found analytically in the weak coupling regime and exactly for an arbitrary impurity coupling strength using numerical tight-binding simulations.
