2013/06/30 by Valentin Stanev, A. E. Koshelev, Alexei E. Koshelev · 29 citations
Materials Science · Mathematics · Physics and Astronomy · #Condensed matter physics #Impurity #Iron-based superconductors research #Mathematics #Pairing #Phase (matter) #Phase diagram #Phase transition #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Rare-earth and actinide compounds #Scattering #State (computer science) #Superconductivity #Symmetry (geometry) #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.89.100505
published in Physical Review B 89(10) (American Physical Society) · 7 pages, 4 figures, several typos fixed, Fig 1 replaced
openalex publication_date 2014/03/31 · arxiv created 2014/04/11 · arxiv updated 2014/04/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We study the role of impurities in a two-band superconductor, and elucidate the nature of the recently predicted transition from the s_\ifmmode±\else\textpm\fi state to the s++ state induced by interband impurity scattering. Using a Ginzburg-Landau theory, derived from microscopic equations, we demonstrate that close to Tc this transition is necessarily a direct one, but deeper in the superconducting state an intermediate complex state appears. This state has a distinct order parameter, which breaks the time-reversal symmetry, and is separated from the s_\ifmmode±\else\textpm\fi and s++ states by continuous phase transitions. Based on our results, we suggest a phase diagram for systems with weak repulsive interband pairing, and discuss its relevance to iron-based superconductors.