Electron trapping by a current vortex

TL;DR

This paper studies how electrons with specific spin orientations can be trapped by magnetic vortices created by electric currents, revealing resonance phenomena and the absence of bound states in weak vortices.

Contribution

It demonstrates that electrons with antiparallel spin can be trapped by strong current vortices regardless of vortex profile, and identifies resonance scattering effects.

Findings

Electrons with antiparallel spin can be trapped by strong vortices.

Resonances occur in electron scattering on the vortex.

No bound states exist for weak vortices.

Abstract

We investigate an electron in the plane interacting with the magnetic field due to an electric current forming a localized rotationally symmetric vortex. We show that independently of the vortex profile an electron with spin antiparallel to the magnetic field can be trapped if the vortex current is strong enough. In addition, the electron scattering on the vortex exhibits resonances for any spin orientation. On the other hand, in distinction to models with a localized flux tube the present situation exhibits no bound states for weak vortices.