论文标题
通量引起的全壳纳米线中的拓扑超导性
Flux-induced topological superconductivity in full-shell nanowires
论文作者
论文摘要
我们提出了一种新的途径，使用磁通量应用于半导体纳米线核心周围的完整超导壳。在破坏性的小公园制度中，超导性的再入区域与壳体中的整数相位数有关。进入核心的隧道揭示了在零相位旋转的零尺寸磁通量附近的硬诱导间隙，并且在一个施加的磁通量子附近的零相位绕组的区域和一个离散的零能量状态，φ_0= h/2e，对应于2π相绕组。理论分析表明，在半导体中存在径向自旋轨道耦合的情况下，超导阶段的绕组可以诱导向支撑Majorana零模式的拓扑阶段过渡。现实的建模显示了在广泛参数上持续存在的拓扑阶段，并重现了实验性隧道电导数据。在全壳纳米岛群岛中，在一个通量量子周围的库仑封锁峰值的进一步测量显示，与设备长度的1E周期性呈指数降低，与纳米线末端的Majorana模式一致。
We present a novel route to realizing topological superconductivity using magnetic flux applied to a full superconducting shell surrounding a semiconducting nanowire core. In the destructive Little-Parks regime, reentrant regions of superconductivity are associated with integer number of phase windings in the shell. Tunneling into the core reveals a hard induced gap near zero applied flux, corresponding to zero phase winding, and a gapped region with a discrete zero-energy state around one applied flux quantum, Φ_0 = h/2e, corresponding to 2π phase winding. Theoretical analysis indicates that in the presence of radial spin-orbit coupling in the semiconductor, the winding of the superconducting phase can induce a transition to a topological phase supporting Majorana zero modes. Realistic modeling shows a topological phase persisting over a wide range of parameters, and reproduces experimental tunneling conductance data. Further measurements of Coulomb blockade peak spacing around one flux quantum in full-shell nanowire islands shows exponentially decreasing deviation from 1e periodicity with device length, consistent with Majorana modes at the ends of the nanowire.
