Angle integrated photoemission study of SmO$_{0.85}$F$_{0.15}$FeAs

TL;DR

This study uses angle-integrated photoemission spectroscopy to analyze the electronic structure of the superconductor SmO$_{0.85}$F$_{0.15}$FeAs, revealing features consistent with an antiferromagnetic ground state and ungapped regions below the transition temperature.

Contribution

First angle-integrated photoemission analysis of SmO$_{0.85}$F$_{0.15}$FeAs revealing its electronic structure and magnetic properties.

Findings

Sharp feature near the Fermi energy

Flat density of states between 0.5 eV and 3 eV

No gap opening below the superconducting transition temperature

Abstract

The electronic structure of the new superconductor, SmO$_{1-x}$F$_x$FeAs ($x=0.15$), has been studied by angle-integrated photoemission spectroscopy. Our data show a sharp feature very close to the Fermi energy, and a relative flat distribution of the density of states between 0.5 eV and 3 eV binding energy, which agrees best with band structure calculations considering an antiferromagnetic ground state. No noticeable gap opening was observed at 12 Kelvin below the superconducting transition temperature, indicating the existence of large ungapped regions in the Brillouin zone.