Josephson π state induced by valley polarization

Jun Wang; Y. H. Yang; K. S. Chan

doi:10.1103/PhysRevB.89.064501

← Back to search

Josephson π state induced by valley polarization

Jun Wang, Y. H. Yang, K. S. Chan

DOI 10.1103/PhysRevB.89.064501 · 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

We theoretically explore possible π-state Josephson junctions made from graphene-like two-dimensional materials (G) with the honeycomb lattice structure. It is shown that the valley polarization in the G sheet could lead to a 0-π state transition of the Josephson junction because of the valley-singlet Cooper pairs acquiring a nonzero momentum. When the valley-mixing scattering exists in the interfaces of the junction due to lattice mismatch, an odd-frequency valley-triplet supercurrent flows in the system even though the G sheet is fully valley polarized, and the supercurrent is characterized by a rapid atomic-scale oscillation with a periodicity of three lattice constants.