Thompson, Michael and Prance, Jonathan and Haley, Richard and Pashkin, Yuri and Ben Shalom, Moshe and Fal'Ko, Vladimir and Matthews, Anthony and White, Jeremy and Viznichenko, Roman and Melhem, Ziad (2017) Superconducting quantum interference devices with graphene junctions. APS March Meeting 2017.
Full text not available from this repository.Abstract
We present measurements of DC superconducting quantum interference devices based on Nb/graphene/Nb Josephson junctions. The superconducting proximity effect in graphene can be used to build Josephson junctions whose critical current can be controlled by field-effect gates. These junctions combine the tunability of semiconductor Josephson junctions with the high critical currents and low contact resistances of metal SNS junctions. By using local gates, the SQUID junction critical currents can be modified individually and this allows the sensitivity and symmetry of the SQUID to be controlled in-situ. We compare the critical current of the SQUID with simulations that include a non-sinusoidal current phase relation in the junctions, as expected for ballistic graphene junctions. We also investigate the transfer function of the device in both symmetric and asymmetric configurations and find a highest transfer function of 300 μV/Φ0. Graphene Josephson junctions have the potential to add functionality to existing technologies; for example, to make SQUID magnetometers with tunable sensitivity or superconducting qubits with fast electrical control.