Graphene-Superconductor Hybrid Devices
Abstract
This project studies the physics and application of the graphene-superconductor hybrid devices. The research work focuses on two aspects: 1) understanding the intrinsic superconducting proximity effect of Dirac electron in graphene; 2) developing novel graphene-superconductor devices for exploring of fundamental science and for frontier technology/applications. 1. We have a devised novel technique which allows fabrication of ultra-high-quality suspended graphene Josephson weak links. With these devices, we demonstrated the signature of the long-standing theoretical prediction of the evanescent charge transport near the Dirac point. 2. We carried out a comprehensive study of the impact of low magnetic field on Andreev reflection at the graphene superconductor interface. Andreev reflection suppression in low magnetic field is found to be strongly affected by the effective superconducting gap at the graphene-superconductor interface and the Abrikosov vortex dynamics. 3. In ultrahigh quality suspended graphene Josephson weak links, which shows well developed quantum Hall plateaus in magnetic field down to approx. 0.1 Tesla, we observed strong suppression of Andreev reflection at the quantum Hall regime. We have devised a new device scheme which couples superconductivity to a quantum Hall antidot in graphene. In our preliminary work on such device, we have been able to localize quantum Hall edge states in such antidot, and demonstrate Aharonov Bohm conductance oscillations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 14, 2019
- Accession Number
- AD1085856
Entities
People
- Xu Du