The role of pressure on the magnetism of bilayer graphene

TL;DR

This study investigates how applying pressure perpendicular to bilayer graphene layers influences the magnetic moments induced by vacancies, revealing that pressure can lower the interaction threshold for magnetization and thus affect magnetic properties.

Contribution

It demonstrates that mechanical pressure can modulate the magnetic behavior of bilayer graphene with vacancies, providing insights into strain-controlled magnetism in layered carbon materials.

Findings

Pressure reduces the critical Hubbard interaction for magnetization.

Magnetic behavior varies with vacancy type under pressure.

Results extend to multilayer graphene and graphite.

Abstract

We study the effect of pressure on the localized magnetic moments induced by vacancies in bilayer graphene in the presence of topological defects breaking the bipartite nature of the lattice. By using a mean-field Hubbard model we address the two inequivalent types of vacancies that appear in the Bernal stacking bilayer graphene. We find that by applying pressure in the direction perpendicular to the layers the critical value of the Hubbard interaction needed to polarize the system decreases. The effect is particularly enhanced for one type of vacancies, and admits straightforward generalization to multilayer graphene in Bernal stacking and graphite. The present results clearly demonstrate that the magnetic behavior of multilayer graphene can be affected by mechanical transverse deformation.