Multiband ballistic transport and anisotropic commensurability magnetoresistance in antidot lattices of AB-stacked trilayer graphene

TL;DR

This study investigates ballistic transport and magnetoresistance in AB-stacked trilayer graphene antidot lattices, revealing band-specific commensurability peaks and anisotropic effects linked to the Fermi surface shape.

Contribution

It demonstrates the first observation of band-dependent commensurability peaks and anisotropic magnetoresistance in trilayer graphene antidot lattices, linking transport features to band structure.

Findings

Commensurability peaks differ between monolayer-like and bilayer-like bands.

Anisotropic magnetoresistance arises from the trigonally warped Fermi surface.

Numerical simulations closely match experimental magnetoresistance data.

Abstract

Ballistic transport was studied in a multiple-band system consisting of an antidot lattice of AB-stacked trilayer graphene. The low temperature magnetoresistance showed commensurability peaks arising from matching of the antidot lattice period and radius of cyclotron orbits for each mono- and bilayer-like band in AB stacked trilayer graphene. The commensurability peak of the monolayer-like band appeared at a lower magnetic field than that of the bilayer-like band, which reflects the fact that the Fermi surface of the bilayer-like band is larger than that of monolayer-like band. Rotation of the antidot lattice relative to the crystallographic axes of graphene resulted in anisotropic magnetoresistance, which reflects the trigonally warped Fermi surface of the bilayer-like band. Numerical simulations of magnetoresistance that assumed ballistic transport in the mono- and bilayer-like bands approximately reproduced the observed magnetoresistance features. It was found that the monolayer-like band significantly contributes to the conductivity even though its carrier density is an order smaller than that of the bilayer-like band. These results indicate that ballistic transport experiments could be used for studying the anisotropic band structure of multiple-band systems.