Investigation of the superconducting gap structure in SrFe 2(As 0.7P 0.3) 2 by magnetic penetration depth and flux flow resistivity analysis

Hideyuki Takahashi, Tatsunori Okada, Yoshinori Imai, Kentaro Kitagawa, Kazuyuki Matsubayashi, Yoshiya Uwatoko, Atsutaka Maeda

Research output: Contribution to journalArticlepeer-review

20 Citations (Scopus)


We measured the microwave surface impedances and obtained the superfluid density and flux flow resistivity in single crystals of a phosphor-doped iron-based superconductor SrFe 2(As 1-xP x) 2 single crystals (x=0.30, T c=25K). At low temperatures, the superfluid density, n s(T)/n s(0), obeys a power law, n s(T)/n s(0)=1-C (T /T c )n, with a fractional exponent of n=1.5-1.6. The flux flow resistivity was significantly enhanced at low magnetic fields. These features are consistent with the presence of line nodes on at least one band and modulated nodeless gap with deep minimum on the same bands and/or other bands. The remarkable difference observed in the superconducting gap structure between SrFe 2(As 1-xP x) 2 and BaFe 2(As 1-xP x) 2 in our experiments is important for clarifying the mechanism of iron-based superconductivity in the 122 system.

Original languageEnglish
Article number144525
JournalPhysical Review B - Condensed Matter and Materials Physics
Issue number14
Publication statusPublished - 2012 Oct 22
Externally publishedYes

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics


Dive into the research topics of 'Investigation of the superconducting gap structure in SrFe <sub>2</sub>(As <sub>0.7</sub>P <sub>0.3</sub>) <sub>2</sub> by magnetic penetration depth and flux flow resistivity analysis'. Together they form a unique fingerprint.

Cite this