Momentum dependence of the superconducting gap in Ba1-xKxFe2As2

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • D. V. Evtushinsky - , Leibniz Institute for Solid State and Materials Research Dresden (Autor:in)
  • D. S. Inosov - , Max Planck Institute for Gravitational Physics (Albert Einstein Institute), Leibniz Institute for Solid State and Materials Research Dresden (Autor:in)
  • V. B. Zabolotnyy - , Leibniz Institute for Solid State and Materials Research Dresden (Autor:in)
  • A. Koitzsch - , Leibniz Institute for Solid State and Materials Research Dresden (Autor:in)
  • M. Knupfer - , Leibniz Institute for Solid State and Materials Research Dresden (Autor:in)
  • B. Buechner - , Leibniz Institute for Solid State and Materials Research Dresden (Autor:in)
  • M. S. Viazovska - , Max Planck Institute for Gravitational Physics (Albert Einstein Institute) (Autor:in)
  • G. L. Sun - , Max Planck Institute for Gravitational Physics (Albert Einstein Institute) (Autor:in)
  • V. Hinkov - , Max Planck Institute for Gravitational Physics (Albert Einstein Institute) (Autor:in)
  • A. V. Boris - , Max Planck Institute for Gravitational Physics (Albert Einstein Institute) (Autor:in)
  • C. T. Lin - , Max Planck Institute for Gravitational Physics (Albert Einstein Institute) (Autor:in)
  • B. Keimer - , Max Planck Institute for Gravitational Physics (Albert Einstein Institute) (Autor:in)
  • A. Varykhalov - , Helmholtz-Zentrum Berlin für Materialien und Energie (HZB) (Autor:in)
  • A. A. Kordyuk - , Leibniz Institute for Solid State and Materials Research Dresden (Autor:in)
  • S. V. Borisenko - , Leibniz Institute for Solid State and Materials Research Dresden (Autor:in)

Abstract

The precise momentum dependence of the superconducting gap in the iron-arsenide superconductor Ba1-xKxFe2As2 (BKFA) with T-c=32 K was determined from angle-resolved photoemission spectroscopy (ARPES) via fitting the distribution of the quasiparticle density to a model. The model incorporates finite lifetime and experimental resolution effects, as well as accounts for peculiarities of BKFA electronic structure. We have found that the value of the superconducting gap is practically the same for the inner Gamma barrel, X pocket, and "blade" pocket, and equals 9 meV, while the gap on the outer Gamma barrel is estimated to be less than 4 meV, resulting in 2 Delta/k(B)T(c)=6.8 for the large gap and 2 Delta/k(B)T(c)< 3 for the small gap. A large (77 +/- 3 %) nonsuperconducting component in the photoemission signal is observed below T-c. Details of gap extraction from ARPES data are discussed in Appendixes A x B.

Details

OriginalspracheEnglisch
Aufsatznummer054517
Seitenumfang13
FachzeitschriftPhysical Review B
Jahrgang79
Ausgabenummer5
PublikationsstatusVeröffentlicht - Feb. 2009
Peer-Review-StatusJa
Extern publiziertJa

Externe IDs

Scopus 61849115238

Schlagworte

Schlagwörter

  • barium compounds, high-temperature superconductors, iron compounds, photoelectron spectra, potassium compounds, quasiparticles, superconducting energy gap

Bibliotheksschlagworte