Fig. 1: The parent topological superconductor with the grain-boundary defect.
a Two misaligned crystalline lattices of a p−wave superconductor form a grain boundary consisting of edge dislocations at their intersection. bL and bR are the Burgers vectors of the two inequivalent edge dislocations, belonging to the left and right sublattice, respectively. b Schematic illustration of the effective 1D superlattice formed by the single dislocation defects along the grain boundary, together with the parameters in the effective Hamiltonian (2). The parameter d (l) indicates the distance between neighboring lattice sites within the same (opposite) sublattice. The competition between the inter-unit cell tba and the intra-unit cell tab pairings drives the topology of the emergent superconductor along the grain boundary, while \(\tilde{\Delta }\) is the next-nearest neighbor intra-unit cell pairing.
