Observation of excited states in a graphene double quantum dot

Abstract

We study a graphene double quantum dot in different coupling regimes. Despite\nthe strong capacitive coupling between the dots, the tunnel coupling is below\nthe experimental resolution. We observe additional structures inside the\nfinite-bias triangles, part of which can be attributed to electronic excited\ndot states, while others are probably due to modulations of the transmission of\nthe tunnel barriers connecting the system to source and drain leads.\n