skip to main content


Title: Superconducting properties of the s ± -wave state: Fe-based superconductors

Although the pairing mechanism of Fe-based superconductors (FeSCs) has not yet been settled with consensus with regard to the pairing symmetry and the superconducting (SC) gap function, the vast majority of experiments support the existence of spin-singlet signchanging s-wave SC gaps on multi-bands (s±-wave state). This multi-band s±-wave state is a very unique gap state per se and displays numerous unexpected novel SC properties, such as a strong reduction of the coherence peak, non-trivial impurity effects, nodal-gap-like nuclear magnetic resonance signals, various Volovik effects in the specific heat (SH) and thermal conductivity, and anomalous scaling behaviors with a SH jump and condensation energy versus Tc, etc. In particular, many of these non-trivial SC properties can easily be mistaken as evidence for a nodal-gap state such as a d-wave gap. In this review, we provide detailed explanations of the theoretical principles for the various non-trivial SC properties of the s±-wave pairing state, and then critically compare the theoretical predictions with experiments on FeSCs. This will provide a pedagogical overview of to what extent we can coherently understand the wide range of different experiments on FeSCs within the s±-wave gap model.
 [1] ;  [2]
  1. Chonnam National Univ., Kwangju (Korea, Republic of)
  2. Univ. of Florida, Gainesville, FL (United States)
Publication Date:
Grant/Contract Number:
Published Article
Journal Name:
Journal of Physics. Condensed Matter
Additional Journal Information:
Journal Volume: 29; Journal Issue: 12; Journal ID: ISSN 0953-8984
IOP Publishing
Research Org:
Univ. of Florida, Gainesville, FL (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; iron-based superconductors, s±-wave pairing state, superconducting properties
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1424735