Skyrmion-resolved topology in chiral topological superconductors
Phys. Rev. B 113, 235426 – Published 18 June, 2026
DOI: https://doi.org/10.1103/3k9g-1gkh
Abstract
Chiral topological superconductors (TSCs) are conventionally characterized by the bulk Chern number, which dictates the number of chiral Majorana modes at the boundary. However, this single invariant often obscures the rich momentum-space structure of the superconducting gap. In this work, we unveil a hidden topological structure in chiral TSCs by resolving the bulk topology at distinct, high-symmetry points in the Brillouin zone. We demonstrate that TSC phases sharing the same Chern number can be topologically different, distinguished by the distribution of Skyrmions at different high-symmetry points in momentum space. Crucially, the interplay between these invariants and particle-hole symmetry gives rise to anomalous helical Majorana edge modes at the boundaries of TSCs, a phenomenon that is forbidden in the standard Chern-number paradigm. By constructing heterostructures between quantum anomalous Hall insulators (QAHIs) and these refined TSC phases, we utilize nonequilibrium Green's functions and the Landauer–Büttiker formalism to identify unique signatures in thermal conductance. Our findings not only resolve the topological ambiguity in conventional TSC classification but also provide a novel pathway to engineer and manipulate robust Majorana modes, offering new degrees of freedom for topological quantum-computing architectures.
