Transport through a Gate Tunable Graphene Double Quantum Dot

We demonstrate how molecular states of coupled graphene quantum dots are probed in transport experiments. The applied method measures the sequential tunneling of electrons through the double dot and hence resolves the molecular state transport channel simultaneously. The overlap of the two dots' wavefunctions, and in turn, the tunnel coupling between the two dots are controlled by the local gates. These results imply the relevance of our graphene device for implementing a quantum manipulation by adjusting the electrodes.