Co-existence of classical snake states and Aharanov-Bohm oscillations along graphene p-n junctions

TL;DR

This study directly compares snake states and Aharonov-Bohm oscillations in encapsulated graphene p-n junctions, revealing their coexistence and providing insights into their distinct characteristics through detailed experimental analysis.

Contribution

It offers the first direct comparison of snake states and Aharonov-Bohm oscillations in the same graphene device, clarifying their signatures and coexistence conditions.

Findings

Snake states and Aharonov-Bohm oscillations can coexist in graphene p-n junctions.

Distinct dependencies on charge density, magnetic field, temperature, and bias were identified.

Aharonov-Bohm oscillations were assigned to specific enclosed areas by edge states.

Abstract

Snake states and Aharonov-Bohm interferences are examples of magnetoconductance oscillations that can be observed in a graphene p-n junction. Even though they have already been reported in suspended and encapsulated devices including different geometries, a direct comparison remains challenging as they were observed in separate measurements. Due to the similar experimental signatures of these effects a consistent assignment is difficult, leaving us with an incomplete picture. Here we present measurements on p-n junctions in encapsulated graphene revealing several sets of magnetoconductance oscillations allowing for their direct comparison. We analysed them with respect to their charge carrier density, magnetic field, temperature and bias dependence in order to assign them to either snake states or Aharonov-Bohm oscillations. Furthermore we were able to consistently assign the various Aharonov-Bohm interferences to the corresponding area which the edge states enclose. Surprisingly, we find that snake states and Aharonov-Bohm interferences can co-exist within a limited parameter range.