English

Josephson junction of minimally twisted bilayer graphene

Mesoscale and Nanoscale Physics 2025-02-18 v2

Abstract

We theoretically investigate the transport properties of Josephson junctions composed of superconductor/minimally twisted bilayer graphene/superconductor structures. In the presence of an out-of-plane electric field, the low energy physics is best described by a network of chiral domain-wall states. Depending on system parameters, they lead to the emergence of zig-zag or pseudo-Landau level modes with distinct transport characteristics. Specifically, we find zig-zag modes feature linear dispersion of Andreev bound states, resulting in a 4π4\pi-periodic Josephson current. In contrast, pseudo-Landau level modes exhibit flat Andreev bound states and, consequently, a vanishing bulk Josephson current. Interestingly, edge states can give rise to 4π4\pi-periodic Josephson response in the pseudo-Landau level regime. We also discuss experimental signatures of such responses.

Keywords

Cite

@article{arxiv.2405.03571,
  title  = {Josephson junction of minimally twisted bilayer graphene},
  author = {Ritajit Kundu and Arijit Kundu},
  journal= {arXiv preprint arXiv:2405.03571},
  year   = {2025}
}

Comments

16 pages, 9 figures