2013/11/22 by A. Vagov, Vagov, A., A. A. Shanenko +10
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Iron-based superconductors research #Physics of Superconductivity and Magnetism #Rare-earth and actinide compounds #Superconductivity (cond-mat.supr-con) #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.1311.5624
submitted to PRL
openalex publication_date 2013/11/22 · arxiv created 2013/12/09 · arxiv updated 2013/12/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Bogomolnyi critical point, originally introduced in string theories, is fundamental to superconductivity. At the critical temperature Tc it marks the sharp border between ideally diamagnetic bulk type-I superconductors and type-II ones that can host vortices, while itself it harbors infinitely degenerate distributions of magnetic flux in the superconducting state. Here we show that below Tc the physics of the Bogomolnyi critical point projects onto a wider range of microscopic parameters, even extremely wide for multiband superconductors. In this critical range, the degeneracy of the superconducting state at Tc is lifted into a sequence of novel topological equilibria and the customary understanding of superconducting phenomena does not suffice. As a radical departure from traditional views, we introduce the paradigm of critical superconductors, discuss their distinct magnetic properties, advocate their subdivision in terms of possible intermediate states, and demonstrate direct relevance of this paradigm to superconducting materials of prime interest today.