1 research outputs found
Spin transport in ferromagnet-InSb nanowire quantum devices
Signatures of Majorana zero modes (MZMs), which are the building blocks for
fault-tolerant topological quantum computing, have been observed in
semiconductor nanowires (NW) with strong spin-orbital-interaction (SOI), such
as InSb and InAs NWs with proximity-induced superconductivity. Realizing
topological superconductivity and MZMs in this most widely-studied platform
also requires eliminating spin degeneracy, which is realized by applying a
magnetic field to induce a helical gap. However, the applied field can
adversely impact the induced superconducting state in the NWs and also places
geometric restrictions on the device, which can affect scaling of future
MZM-based quantum registers. These challenges could be circumvented by
integrating magnetic elements with the NWs. With this motivation, in this work
we report the first experimental investigation of spin transport across InSb
NWs, which are enabled by devices with ferromagnetic (FM) contacts. We observe
signatures of spin polarization and spin-dependent transport in the
quasi-one-dimensional ballistic regime. Moreover, we show that electrostatic
gating tunes the observed magnetic signal and also reveals a transport regime
where the device acts as a spin filter. These results open an avenue towards
developing MZM devices in which spin degeneracy is lifted locally, without the
need of an applied magnetic field. They also provide a path for realizing
spin-based devices that leverage spin-orbital states in quantum wires.Comment: 30 pages, 12 figure