Loss and Decoherence at the Quantum Hall-Superconductor Interface

We perform a systematic study of Andreev conversion at the interface between a superconductor and graphene in the quantum Hall (QH) regime. We find that the probability of Andreev conversion from electrons to holes follows an unexpected but clear trend: the dependencies on temperature and magnetic field are nearly decoupled. We discuss these trends and the role of the superconducting vortices, whose normal cores could both absorb and dephase the individual electrons in a QH edge. Our Letter may pave the road to engineering a future generation of hybrid devices for exploiting superconductivity proximity in chiral channels.

Automated summary

In this study, we systematically investigate Andreev conversion between a superconductor and graphene in the quantum Hall regime. We discover an unexpected and clear trend in the probability of electron-to-hole Andreev conversion, with temperature and magnetic field showing nearly decoupled dependencies. We also discuss the role of superconducting vortices and their impact on individual electrons in the quantum Hall edge.