Dissemin is shutting down on January 1st, 2025

Published in

American Physical Society, Physical review B, 18(85), 2012

DOI: 10.1103/physrevb.85.184519

Links

Tools

Export citation

Search in Google Scholar

Unconventional superconducting gap via spin fluctuations in iron-vacancy-orderedAyFe2−xSe2

Journal article published in 2012 by Shin-Ming Huang ORCID, Chung-Yu Mou
This paper is available in a repository.
This paper is available in a repository.

Full text: Download

Green circle
Preprint: archiving allowed
Green circle
Postprint: archiving allowed
Green circle
Published version: archiving allowed
Data provided by SHERPA/RoMEO

Abstract

Based on an effective 12-orbital tight-binding model, we examine the superconducting states induced by the antiferromagnetic fluctuations for iron-vacancy-ordered A$_{y}$Fe$_{2-x}$Se$_{2}$. It is shown that due to the broken reflection symmetry induced by the iron vacancies, new superconducting states with $C_{4h}$ symmetry emerge. In particular, we show that in the $C_{4h}$ symmetry, symmetric axes of the pairing momenta do not need to coincide with axes of the unit cell. As a result, in addition to the magnitude of the pairing gap, the relative orientation of the pairing wave function to the lattice forms another degree of freedom for characterizing the superconducting gap and can further help in gaining the condensation energy. Nonetheless, similar to other iron-based superconductors, the singlet ground state is still dominated by s-wave or d-wave, which are nearly degenerate with anisotropic gaps. Furthermore, s-wave and d-wave superconducting states are separated by a quantum critical point controlled by the Hund's rule coupling $J_{H}$. ; Comment: 9 pages, 8 figures