Fluxoid valve effect in full-shell nanowire Josephson junctions

Abstract

We introduce a new type of supercurrent valve based on full-shell nanowires. These hybrid wires consist of a semiconductor core fully wrapped in a thin superconductor shell and subjected to an axial magnetic field. Due to the tubular shape of the shell, the superconductor phase acquires an integer number $n$ of $2\pi$ twists or \textit{fluxoids} that increases in steps with applied flux. By connecting two such hybrid wires, forming a Josephson junction (JJ), a flux-modulated supercurrent develops. If the two superconducting sections of the JJ have different radii $R_1$ and $R_2$, they can develop equal or different fluxoid numbers $n_1,n_2$ depending on the field. If $n_1\ne n_2$ the supercurrent is blocked, while it remains finite for $n_1=n_2$. This gives rise to a fluxoid valve effect controlled by the applied magnetic field or a gate voltage at the junction. We define a fluxoid-valve quality factor that is perfect for cylindrically symmetric systems and decreases as this symmetry is reduced. We further discuss the role of Majorana zero modes at the junction when the full-shell nanowires are in the topological superconducting regime.

8 pages, 4 figures

References in corpus (12)

• Epitaxy of Semiconductor-Superconductor nanowires
• Pseudospin valve in bilayer graphene: towards graphene-based pseudospintronics
• Conduction Channels of an InAs-Al nanowire Josephson weak link
• Electronic structure of full-shell InAs/Al hybrid semiconductor-superconductor nanowires: Spin-orbit coupling and topological phase space
• Asymmetric Little-Parks Oscillations in Full Shell Double Nanowires
• Multiple topological transitions driven by the interplay of normal scattering and Andreev scattering
• Josephson effect and critical currents in trivial and topological full-shell hybrid nanowires
• Absence of Majorana oscillations in finite-length full-shell hybrid nanowires
• Subgap transport in superconductor--semiconductor hybrid islands: Weak and strong coupling regimes
• InP/GaSb core-shell nanowires: a novel hole-based platform with strong spin-orbit coupling for full-shell hybrid devices
• Half-metallic magnetism and the search for better spin valves
• Interplay between evanescent scattering modes and finite dispersion in superconducting junctions

Cited by in corpus (3)

• Solitonic Andreev spin qubits from Andreev states in Corbino Josephson junctions
• Absence of Quasi-Majorana False Positives in Full-Shell Hybrid Nanowires
• Fluxoid solitons in superconducting tapered tubes and bottlenecks