Nonlinear magnetization of graphene

TL;DR

This paper analyzes the nonlinear magnetization behavior of graphene under magnetic fields, considering effects like temperature, disorder, and a possible mass gap, highlighting conditions for experimental observation.

Contribution

It provides a theoretical calculation of graphene's magnetization non-linearity in magnetic fields, including effects of disorder, interactions, and a mass gap.

Findings

Magnetization exhibits non-linear behavior as a function of magnetic field.

Non-linearity becomes observable at fields of a few Teslas to 30 Teslas depending on sample quality.

Disorder and interactions influence the magnetization response.

Abstract

We compute the magnetization of graphene in a magnetic field, taking into account for generality the possibility of a mass gap. We concentrate on the physical regime where quantum oscillations are not observed due to the effect of the temperature or disorder and show that the magnetization exhibits non-linear behaviour as a function of the applied field, reflecting the strong non-analyticity of the two-dimensional effective action of Dirac electrons. The necessary values of the magnetic field to observe this non-linearity vary from a few Teslas for very clean suspended samples to 20 - 30 Teslas for good samples on substrate. In the light of these calculations, we discuss the effects of disorder and interactions as well as the experimental conditions under which the predictions can be observed.