At low temperatures, a superconducting current that flows through a graphene layer sandwiched between two superconducting electrodes can be carried by either electrons or by holes, depending on the gate voltage that determines the charge density in the graphene layer. Interestingly, this finds that a finite supercurrent can flow even when the charge density is zero.
- Hubert B. Heersche
- Pablo Jarillo-Herrero
- Alberto F. Morpurgo
