论文标题
在拓扑上琐碎的旋转轨道耦合纳米线中，大群岛状的局部旋转密度没有结合状态
Majorana-like localized spin density without bound states in topologically trivial spin-orbit coupled nanowires
论文作者
论文摘要
在自旋轨道耦合的纳米线的拓扑阶段中，主要构造状态在纳米线边缘定位，并表现出与磁场和旋转轨道场的旋转密度正交。通过调查暴露于具有不同自旋轨耦合区域之间界面的均匀磁场的纳米线，我们发现即使两个接口侧都在拓扑上琐碎的相位，即使没有绑定状态，正交旋转密度也会固定在界面上。微不足道的结合状态可能还会出现在接口上，尤其是如果自旋轨道耦合在界面上的符号相反时。但是，可以通过平行于自旋轨道场平行的自旋轨道曲线的平滑来破坏它。相反，正交旋转密度持续到各种逼真的参数范围。我们还表明，虽然到目前为止，虽然散装平衡旋转电流的测量一直难以捉摸，但这种强大的正交旋转密度峰值可能提供了一种检测跨接口的旋转电流变化的方法。
In the topological phase of spin-orbit coupled nanowires Majorana bound states are known to localize at the nanowire edges and to exhibit a spin density orthogonal to both the magnetic field and the spin-orbit field. By investigating a nanowire exposed to a uniform magnetic field with an interface between regions with different spin-orbit couplings, we find that the orthogonal spin density is pinned at the interface even when both interface sides are in the topologically trivial phase, and even when no bound state is present at all. A trivial bound state may additionally appear at the interface, especially if the spin-orbit coupling takes opposite signs across the interface. However, it can be destroyed by a smoothening of the spin-orbit profile or by a magnetic field component parallel to the spin-orbit field. In contrast, the orthogonal spin density persists in various and realistic parameter ranges. We also show that, while the measurement of bulk equilibrium spin currents has been elusive so far, such robust orthogonal spin density peak may provide a way to detect spin current variations across interfaces.
