QHE and Superconductivity

The quantum Hall effect and superconductivity are two remarkable examples of matter excitation traveling over macroscopic distance with no dissipation. The charged particles in these electronic phases do not waste any energy while flowing across many lattice sites in a far-from-perfect medium.

Their unexpected discovery, followed by the discovery of high-Tc superconductors and the fractional quantum Hall effect (also not predicted), helped physicist to understand the consequences of quantum mechanics and promoted entirely new technological venues.

We are interested in the interface of the two phases, where we hope to induce superconducting correlations in a spin polarized quantum Hall channel formed in a particular graphene structure. Under certain conditions, new type of excitation are predicted which may allow a protected quantum information unit for future computers.


Ballistic Josephson currents under high magnetic fields. Nphys 3592

In a previous work, superconducting correlations induced in graphene were found to persist, in principle, up to the onset of the QHE at high magnetic fields. We think that a modified version of a graphene-superconductor interface will allow us to test the predictions of the unique excitation emerging in this system.