Tunneling break-junction spectroscopy on the superconductor NdFeAs(O 0.9F0.1)

Toshikazu Ekino, Akira Sugimoto, Hirotaka Okabe, Kazuhiro Shohara, Ryuichi Ukita, Jun Akimitsu, Alexander M. Gabovich

Research output: Contribution to journalArticlepeer-review

13 Citations (Scopus)


Tunnel break-junction method has been adopted to study polycrystalline samples of iron-oxypnictide superconductor NdFeAs(O0.9F 0.1) with Tc=48K. Measurements were carried out at 4.2 K. Break-junction (BJ) conductance versus voltage curves showed gap-edge peaks with the peak-to-peak distances Vp-p=4Δ/e=28-40mV at 4.2 K, where 2Δ(T) is the superconducting energy gap, e>0 is the elementary charge. This yields 2Δ(0)=14-20meV, so that the gap ratio 2Δ(0)/kBTc is about 4.1±0.7,kB being the Boltzmann constant. This ratio implies strong-coupling superconductivity in the framework of Bardeen-Cooper-Schrieffer theory, being, however, much smaller than that for high-Tc copper oxides. This suggests a significant difference in the pairing mechanism between those classes of materials.

Original languageEnglish
Pages (from-to)S358-S359
JournalPhysica C: Superconductivity and its applications
Issue numberSUPPL.1
Publication statusPublished - Dec 2010
Externally publishedYes


  • Break-junction
  • Energy gap
  • Iron-oxypnictide superconductors
  • Tunneling

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Energy Engineering and Power Technology
  • Electrical and Electronic Engineering


Dive into the research topics of 'Tunneling break-junction spectroscopy on the superconductor NdFeAs(O 0.9F0.1)'. Together they form a unique fingerprint.

Cite this