Atomic-scale control of graphene magnetism using hydrogen atoms

TL;DR

This study demonstrates that single hydrogen atoms on graphene induce localized magnetic moments and long-range magnetic coupling, which can be manipulated with atomic precision using STM techniques.

Contribution

It provides experimental and theoretical evidence of hydrogen-induced magnetism on graphene and shows how to control it at the atomic scale.

Findings

Hydrogen adsorption induces a ~20 meV spin-split state at the Fermi energy.

Magnetic moments are localized on the carbon sublattice opposite to the H atom.

STM manipulation allows for tailoring graphene's magnetic properties.

Abstract

Isolated hydrogen atoms absorbed on graphene are predicted to induce magnetic moments. Here we demonstrate that the adsorption of a single hydrogen atom on graphene induces a magnetic moment characterized by a ~20 meV spin-split state at the Fermi energy. Our scanning tunneling microscopy (STM) experiments, complemented by first-principles calculations, show that such a spin-polarized state is essentially localized on the carbon sublattice complementary to the one where the H atom is chemisorbed. This atomically modulated spin-texture, which extends several nanometers away from the H atom, drives the direct coupling between the magnetic moments at unusually long distances. Using the STM tip to manipulate H atoms with atomic precision, we demonstrate the possibility to tailor the magnetism of selected graphene regions.