Transport through a network of topological states in twisted bilayer graphene

TL;DR

This paper demonstrates coherent electronic transport through a network of topologically protected states in twisted bilayer graphene, revealing robust quantum oscillations indicative of one-dimensional conduction channels.

Contribution

It provides experimental evidence of topologically protected, one-dimensional charge flow in twisted bilayer graphene, a novel observation in moiré materials.

Findings

Observation of Fabry-Pérot and Aharonov-Bohm oscillations in magnetic fields up to 8T

Charge carriers flow in topologically protected, one-dimensional channels

Persistence of quantum oscillations indicates robust topological states

Abstract

We explore a network of electronic quantum valley Hall (QVH) states in the moir\'e crystal of minimally twisted bilayer graphene. In our transport measurements we observe Fabry-P\'erot and Aharanov-Bohm oscillations which are robust in magnetic fields ranging from 0 to 8T, in strong contrast to more conventional 2D systems where trajectories in the bulk are bent by the Lorentz force. This persistence in magnetic field and the linear spacing in density indicate that charge carriers in the bulk flow in topologically protected, one dimensional channels. With this work we demonstrate coherent electronic transport in a lattice of topologically protected states.