Landau Levels and Band Bending in Few-Layer Epitaxial Graphene

TL;DR

This study investigates how magnetic fields and STM probing influence charge distribution in few-layer epitaxial graphene, revealing layer charge rearrangements and Landau level formation.

Contribution

We provide a theoretical analysis of charge redistribution and Landau level formation in few-layer graphene under magnetic fields and STM influence, highlighting the role of buried layers.

Findings

Charge tends to rearrange between layers under magnetic fields.

Most layers have filling factors pinned at integer values.

Insights into the role of buried layers in STM studies.

Abstract

The carrier density distributions in few-layer-graphene systems grown on the carbon face of silicon carbide can be altered by the presence of a scanning tunneling microscope (STM) tip used to probe top-layer electronic properties, and by a perpendicular magnetic field which induces well-defined Landau levels. Hartree approximation calculations in the perpendicular field case show that charge tends to rearrange between the layers so that the filling factors of most layers are pinned at integer values. We use our analysis to provide insight into the role of buried layers in recent few-layer-graphene STM studies and discuss the limitations of our model.