The renormalization group plays an essential role in many areas of physics, both
conceptually and as a practical tool to determine the long-distance low-energy properties of …

Kamihara and coworkers' report of superconductivity at T c= 26 K in fluorine-doped
LaFeAsO inspired a worldwide effort to understand the nature of the superconductivity in this …

Emergent electronic phenomena in iron-based superconductors have been at the forefront
of condensed matter physics for more than a decade. Much has been learned about the …

The recently discovered Fe-pnictide and chalcogenide superconductors display low-
temperature properties suggesting superconducting gap structures which appear to vary …

I review recent works on the symmetry and the structure of the superconducting gap in Fe-
based superconductors (FeSCs) and on the underlying pairing mechanism in these …

High-transition temperature (high-T c) superconductivity in the iron pnictides or
chalcogenides emerges from the suppression of the static antiferromagnetic order in their …

Numerous correlated electron systems exhibit a strongly scale-dependent behavior. Upon
lowering the energy scale, collective phenomena, bound states, and new effective degrees …

In iron pnictides, we find that the moderate electron-phonon interaction due to the Fe-ion
oscillation can induce the critical d-orbital fluctuations, without being prohibited by the …

I review theoretical ideas and implications of experiments for the gap structure and symmetry
of the Fe-based superconductors. Unlike any other class of unconventional …

The development of sensible microscopic models is essential to elucidate the normal-state
and superconducting properties of the iron-based superconductors. Because these …