2020/02/29 by Lorenzo Rossi, Fabrizio Dolcini, Fausto Rossi
Materials Science · Mathematics · Physics and Astronomy · #Bound state #Condensed matter physics #Coupling (piping) #Field (mathematics) #Graphene research and applications #Local density of states #MAJORANA #Magnetic field #Materials science #Mathematics #Nanowire #Orbit (dynamics) #Physics #Quantum and electron transport phenomena #Quantum mechanics #Spin (aerodynamics) #Spin–orbit interaction #Superconductivity #Topological Materials and Phenomena #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.101.195421
published as Phys. Rev. B 101, 195421 (2020) · 18 pages, 7 figures
openalex publication_date 2020/05/13 · arxiv created 2020/05/15 · arxiv updated 2020/05/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
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.