Rashba effect in the graphene/Ni(111) system

TL;DR

This study demonstrates a significant Rashba effect in graphene on Ni(111), showing how electron spins in graphene can be manipulated via interface electric fields, with implications for spintronic device development.

Contribution

It provides experimental evidence of a large Rashba effect in graphene/Ni(111), revealing a new method to control electron spins in graphene for spintronics.

Findings

Energy shift up to 225 meV with magnetization reversal

Rashba interaction causes strong spin-dependent energy shifts

Potential for controlled spin manipulation in graphene devices

Abstract

Here, we report on angle-resolved photoemission studies of the electronic $\pi$ states of high-quality epitaxial graphene layer on a Ni(111) surface. In this system electron binding energy of the $\pi$ states shows a strong dependence on the magnetization reversal of the Ni film. The observed extraordinary large energy shift up to 225 meV of the graphene-derived $\pi$-band peak position for opposite magnetization directions is attributed to a manifestation of the Rashba interaction of spin-polarized electrons in the $\pi$ band with the large effective electric field at graphene/Ni interface. Our findings show that an electron spin in the graphene layer can be manipulated in a controlled way and have important implications for graphene-based spintronic devices.