Ballistic edge states in Bismuth nanowires revealed by SQUID   interferometry
  Spin-orbit interactions are known to have drastic effects on the band structure of heavy-element-based materials. Celebrated examples are the recently identified 3D and 2D topological insulators. In those systems transport takes place at surfaces or along edges, and spin-momentum locking provides protection against (non-magnetic) impurity scattering, favoring spin-polarized ballistic transport. We have used the measurement of the current phase relation of a micrometer-long single crystal bismuth nanowire connected to superconducting electrodes, to demonstrate that transport occurs ballistically along two edges of this high-spin-orbit material. In addition, we show that a magnetic field can induce to 0-pi transitions and phi0-junction behavior, thanks to the extraordinarily high g-factor and spin orbit coupling in this system, providing a way to manipulate the phase of the supercurrent-carrying edge states. 
Anil Murani, Alik Kasumov, Shamashis Sengupta, Yu.A. Kasumov,   V.T.Volkov, I.I. Khodos, F. Brisset, Rapha\"elle Delagrange,...
cond-mat.mes-hall