Actualités

Absence of edge reconstruction for quantum Hall edge channels in graphene devices

In 1982, two years after the discovery of the quantum Hall effect, B. Halperin predicted the existence of edge states carrying the electron flow along the sample periphery. These edge states, which form unidirectional (chiral) ballistic conduction channels, have been pivotal in understanding most of the transport properties of the quantum Hall effect. In our work, we reveal the real-space structure of the quantum Hall edge channels in graphene by performing scanning tunneling microscopy and spectroscopy at the edge of a graphene flake under high magnetic field.