T Nomura et al 2008 Supercond. Sci. Technol. 21 125028 doi:10.1088/0953-2048/21/12/125028
Crystallographic phase transition and high-Tc superconductivity in LaFeAsO:F
T Nomura1, S W Kim2, Y Kamihara3, M Hirano3, P V Sushko4,5, K Kato6, M Takata6, A L Shluger4,5 and H Hosono1,3,7,8
Show affiliationsUndoped LaFeAsO, the parent compound of the newly found high-Tc superconductor, exhibits a sharp decrease in the temperature-dependent resistivity at ~160 K. The anomaly can be suppressed by F doping with simultaneous appearance of superconductivity appears correspondingly, suggesting a close association of the anomaly with the superconductivity. We examined the crystal structures, magnetic properties and conductivity of undoped (normal conductor) and 14 at.% F-doped LaFeAsO (Tc = 20 K) by synchrotron x-ray diffraction (XRD), DC magnetic measurements, and ab initio calculations demonstrated that the anomaly is associated with a phase transition from tetragonal (P4/nmm) to orthorhombic (Cmma) phases at ~160 K as well as an antiferromagnetic spin ordering transition at ~140 K. These transitions can be explained by spin configuration-dependent potential energy surfaces derived from the ab initio calculations. The suppression of the transitions is ascribed to interrelated effects of geometric and electronic structural changes due to doping by F− ions.
- PACS
-
74.25.Dw Superconductivity phase diagrams
74.62.Bf Effects of material synthesis, crystal structure, and chemical composition
74.62.Dh Effects of crystal defects, doping and substitution
74.25.Fy Transport properties (electric and thermal conductivity, thermoelectric effects, etc.)
74.72.-h Cuprate superconductors (high-Tc and insulating parent compounds)
- Subjects
- Dates
-
Issue 12 (December 2008)
Received 12 October 2008, in final form 31 October 2008
Published 19 November 2008
-
Crystallographic phase transition and high-Tc superconductivity in LaFeAsO:F
T Nomura et al 2008 Supercond. Sci. Technol. 21 125028
-
Florida electro-mechanical cable model of Nb3Sn CICCs for high-field magnet design
Yuhu Zhai and Mark D Bird 2008 Supercond. Sci. Technol. 21 115010
-
Superconductivity at 53.5 K in GdFeAsO1−δ
Jie Yang et al 2008 Supercond. Sci. Technol. 21 082001
-
The effects of bending strain on the critical current and AC loss of BSCCO/Ag tapes
Guo Min Zhang et al 2004 Supercond. Sci. Technol. 17 1018
-
Role of HTS devices in greenhouse gas emission reduction
Teemu Hartikainen et al 2003 Supercond. Sci. Technol. 16 963
-
Magnetization and transport properties of silver-sheathed (Hg, Re)Ba2Ca2Cu3O8+δ tapes
J H Su et al 2003 Supercond. Sci. Technol. 16 1134
-
Real-time magneto-optical imaging of vortices in superconducting NbSe2
Pål Erik Goa et al 2001 Supercond. Sci. Technol. 14 729
-
Microscopic measurement of penetration depth in
thin films by scanning Hall probe microscopy
A Oral et al 1997 Supercond. Sci. Technol. 10 17
-
Radiation quantities and units—understanding the sievert
P J Allisy-Roberts 2005 J. Radiol. Prot. 25 97
-
On collective dose
Bo Lindell 2000 J. Radiol. Prot. 20 1
Users also read
What's this?- Structural and magnetic phase transitions in the ternary iron arsenides SrFe2As2 and EuFe2As2
- Superconductivity in the iron-based F-doped layered quaternary compound Nd[O1 − x Fx]FeAs
- Synthesis and microstructural studies of iron oxypnictide LaO1−xFxFeAs superconductors
Related review articles
What's this?- Unified scaling law for flux pinning in practical superconductors: I. Separability postulate, raw scaling data and parameterization at moderate strains*
- An overview on iron based superconductors
- Probing multiband superconductivity by point-contact spectroscopy