$\pi$-Electron Ferromagnetism in Metal Free Carbon Probed by Soft X-Ray Dichroism

TL;DR

This study uses soft X-ray dichroism to demonstrate that ferromagnetism in proton-irradiated metal-free carbon originates specifically from the carbon π-electron system, providing insight into magnetic order in light elements.

Contribution

It provides direct spectromicroscopy evidence that the magnetic order in proton-irradiated carbon is due to the carbon π-electron system, a novel finding in carbon magnetism research.

Findings

Magnetic order in proton-irradiated carbon originates from the π-electron system.

Room temperature spectromicroscopy confirms the elemental and chemical specificity of the magnetic order.

The study clarifies the origin of ferromagnetism in light-element materials like carbon.

Abstract

Elemental carbon represents a fundamental building block of matter and the possibility of ferromagnetic order in carbon attracted widespread attention. However, the origin of magnetic order in such a light element is only poorly understood and has puzzled researchers. We present a spectromicroscopy study at room temperature of proton irradiated metal free carbon using the elemental and chemical specificity of x-ray magnetic circular dichroism (XMCD). We demonstrate that the magnetic order in the investigated system originates only from the carbon $\pi$-electron system.