Diamagnetism in disordered graphene

TL;DR

This paper investigates the orbital diamagnetism in disordered graphene, revealing a highly diamagnetic susceptibility near zero energy and analyzing the transition from strong magnetic fields to zero field.

Contribution

It provides a theoretical analysis of magnetization in disordered graphene using the effective mass approximation and self-consistent Born approximation, highlighting the singular behavior at zero energy.

Findings

Susceptibility is highly diamagnetic near zero energy.

Magnetic oscillations diminish and converge to susceptibility as field decreases.

Zero-energy behavior is highly singular.

Abstract

The orbital magnetism is studied in graphene monolayer within the effective mass approximation. In models of short-range and long-range disorder, the magnetization is calculated with self-consistent Born approximation. In the zero-field limit, the susceptibility becomes highly diamagnetic around zero energy, while it has a long tail proportional to the inverse of the Fermi energy. We demonstrated how the magnetic oscillation vanishes and converges to the susceptibility, on going from a strong-field regime to zero-field. The behavior at zero energy is shown to be highly singular.