%0 Journal Article
%T Gap opening and orbital modification of superconducting FeSe above the structural distortion
%A Y. -C. Wen
%A K. -J. Wang
%A H. -H. Chang
%A J. -Y. Luo
%A C. -C. Shen
%A H. -L. Liu
%A C. -K. Sun
%A M. -J. Wang
%A M. -K. Wu
%J Physics
%D 2012
%I arXiv
%R 10.1103/PhysRevLett.108.267002
%X We utilize steady-state and transient optical spectroscopies to examine the responses of nonthermal quasiparticles with respect to orbital modifications in normal-state iron-chalcogenide superconductors. The dynamics shows the emergence of gap-like quasiparticles (associated to a ~36 meV energy gap) with a coincident transfer of the optical spectral weight in the visible range, at temperatures above the structural distortion. Our observations suggest that opening of the high-temperature gap and the lattice symmetry breaking are possibly driven by short-range orbital and/or charge orders, implicating a close correlation between electronic nematicity and precursor order in iron-based superconductors.
%U http://arxiv.org/abs/1202.0658v1