Plateau insulator transition in graphene

TL;DR

This paper investigates the quantum Hall effect in graphene under high magnetic fields, revealing a metal-insulator transition with a universal scaling exponent consistent with other two-dimensional systems.

Contribution

It reports the observation of a plateau-insulator transition in graphene and measures its universal scaling exponent, confirming its two-dimensional nature.

Findings

Identified a metal-insulator transition at filling factor ν=0

Measured the universal scaling exponent κ=0.57

Confirmed the universality of the transition in graphene

Abstract

The quantum Hall effect in a single-layer graphene sample is studied in strong magnetic fields up to 28 T. Our measurements reveal the existence of a metal- insulator transition from filling factor $\nu=-2$ to $\nu=0$. The value of the universal scaling exponent is found to be $\kappa=0.57 $ in graphene and therefore in a truly two-dimensional system. This value of $\kappa$ is in agreement with the accepted universal value for the plateau-insulator transitions in standard quasi two-dimensional electron and hole gases.