Superconducting current and proximity effect in ABA and ABC multilayer graphene Josephson junctions

W. A. Muñoz; L. Covaci; F. M. Peeters

doi:10.1103/PhysRevB.88.214502

← Back to search

Superconducting current and proximity effect in ABA and ABC multilayer graphene Josephson junctions

W. A. Muñoz, L. Covaci, F. M. Peeters

DOI 10.1103/PhysRevB.88.214502 · Physical Review B

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

Using a numerical tight-binding approach based on the Chebyshev–Bogoliubov–de Gennes method we describe Josephson junctions made of multilayer graphene contacted by top superconducting gates. Both Bernal (ABA) and rhombohedral (ABC) stacking are considered and we find that the type of stacking has a strong effect on the proximity effect and the supercurrent flow. For both cases the pair amplitude shows a polarization between dimer and nondimer atoms, being more pronounced for rhombohedral stacking. Even though the proximity effect in nondimer sites is enhanced when compared to single-layer graphene, we find that the supercurrent is suppressed. The spatial distribution of the supercurrent shows that for Bernal stacking the current flows only in the topmost layers while for rhombohedral stacking the current flows throughout the whole structure.