Designing Electron Spin Textures and Spin Interferometers by Shape Deformations

TL;DR

This paper shows how changing the shape of a nanoscale ring with Rashba spin-orbit coupling can control electron spin textures and interference effects, enabling all-electrical and geometrical manipulation of spin states.

Contribution

It introduces a method to manipulate electron spin textures through shape deformations in nanostructures with Rashba coupling, revealing topological spin patterns and their impact on spin transport.

Findings

Shape deformations induce complex 3D spin textures.

Topological spin windings can be tuned by geometry.

Spin textures influence electronic interference and transport.

Abstract

We demonstrate that the spin orientation of an electron propagating in a one-dimensional nanostructure with Rashba spin-orbit (SO) coupling can be manipulated on demand by changing the geometry of the nanosystem. Shape deformations that result in a non-uniform curvature give rise to complex three-dimensional spin textures in space. We employ the paradigmatic example of an elliptically deformed quantum ring to unveil the way to get an all-geometrical and all-electrical control of the spin orientation. The resulting spin textures exhibit a tunable topological character with windings around the radial and the out-of-plane directions. We show that these topologically non trivial spin patterns affect the spin interference effect in the deformed ring, thereby resulting in different geometry-driven ballistic electronic transport behaviors. Our results establish a deep connection between electronic spin textures, spin transport and the nanoscale shape of the system.