Topological Bardeen–Cooper–Schrieffer theory of superconducting quantum rings Elena Landrò, Vladimir M. Fomin and Alessio Zaccone Eur. Phys. J. B, 98 1 (2025) 7 Published online: 15 January 2025 DOI: 10.1140/epjb/s10051-024-00851-9