Magnetic adatom induced skyrmion-like spin texture in surface electron waves

TL;DR

This paper demonstrates that a single magnetic adatom on a surface can induce a skyrmion-like spin texture in surface electron waves, revealing the Rashba effect through spin-magnetization patterns detectable by scanning tunneling microscopy.

Contribution

It introduces a novel way to visualize the Rashba effect via spin textures induced by magnetic adatoms, which was previously thought to be undetectable in charge oscillations.

Findings

Magnetic adatoms induce twisted spin textures in surface electrons.

Skyrmionic waves of opposite chirality are superimposed around the adatom.

The Rashba effect can be visualized through induced spin-magnetization patterns.

Abstract

When a foreign atom is placed on a surface of a metal, the surrounding sea of electrons responds screening the additional charge leading to oscillations or ripples. On surfaces, those electrons are sometimes confined to two-dimensional surface states, whose spin-degeneracy is lifted due to the Rashba effect arising from the spin-orbit interaction of electrons and the inversion asymmetric environment. It is believed that at least for a single adatom scanning tunneling microscopy measurements are insensitive to the Rashba splitting i.e. no signatures in the charge oscillations will be observed. Resting on scattering theory, we demonstrate that, if magnetic, one single adatom is enough to visualize the presence of the Rashba effect in terms of an induced spin-magnetization of the surrounding electrons exhibiting a twisted spin texture described as superposition of two skyrmionic waves of opposite chirality.