Abstract
High-temperature superconductivity appears as a consequence of doping charge carriers into an undoped parent compound exhibiting antiferromagnetic order; therefore, ground-state properties of the parent compound are highly relevant to the superconducting state1,2. On the basis of this logic, spin fluctuations have been considered as the origin of pairing of the superconducting electrons in the cuprates1. As possible pairing mechanisms, there is growing interest in unconventional spin fluctuations or advanced orbital fluctuations owing to the characteristic multi-orbital states in iron pnictides3,4,5,6. Here, we report the discovery of an antiferromagnetic phase as well as a unique structural transition in electron-overdoped LaFeAsO1−xHx (x ∼ 0.5), whereby a second parent phase is uncovered, albeit heavily doped. The unprecedented two-dome superconducting phases observed in this material can be interpreted as a consequence of the carrier doping starting from the original x ∼ 0 and additional x ∼ 0.5 parent phases towards the intermediate region7. The bipartite parent phases with distinct physical properties in the second magnetic phase provide us with an interesting example to illustrate the intimate interplay between the magnetic interaction, structural change and orbital degree of freedom in iron pnictide superconductors.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 12 print issues and online access
$259.00 per year
only $21.58 per issue
Buy this article
- Purchase on SpringerLink
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Lee, A. P., Nagaosa, N & Wen, X-G. Doping a Mott insulator: Physics of high-temperature superconductivity. Rev. Mod. Phys. 78, 17–85 (2006).
Paglione, J. & Greene, R. L. High-temperature superconductivity in iron-based materials. Nature Phys. 6, 645–658 (2010).
Singh, D. J. & Du, M-H. Density functional study of LaFeAsO1−xFx: A low carrier density superconductor near itinerant magnetism. Phys. Rev. Lett. 100, 237003 (2008).
Kuroki, K. et al. Unconventional pairing originating from disconnected Fermi surfaces of superconducting LaFeAsO1−xFx . Phys. Rev. Lett. 101, 087004 (2008).
Mazin, I., Singh, D. J., Johannes, M. D. & Du, M. H. Unconventional superconductivity with a sign reversal in the order parameter of LaFeAsO1−xFx . Phys. Rev. Lett. 101, 057003 (2008).
Kontani, H. & Onari, S. Orbital-fluctuation-mediated superconductivity in iron pnictides: Analysis of the five-orbital Hubbard–Holstein model. Phys. Rev. Lett. 104, 157001 (2010).
Iimura, S. et al. Two-dome structure in electron-doped iron arsenide superconductors. Nature Commun. 3, 943 (2012).
Kamihara, Y. et al. Iron-based layered superconductor: LaOFeP. J. Am. Chem. Soc. 128, 10012–10013 (2006).
Kamihara, Y., Watanabe, T., Hirano, M. & Hosono, H. Iron-based layered superconductor La[O1−xFx]FeAs (x=0.05−0.12) with Tc= 26 K. J. Am. Chem. Soc. 130, 3296–3297 (2008).
Chen, X. H. et al. Superconductivity at 43 K in SmFeAsO1−xFx . Nature 453, 761–762 (2008).
Takahashi, H. et al. Superconductivity at 43 K in an iron-based layered compound LaO1−xFxFeAs. Nature 453, 376–378 (2008).
Rotter, M., Tegel, M. & Johrendt, D. Superconductivity at 38 K in the iron arsenide (Ba1−xKx)Fe2As2 . Phys. Rev. Lett 101, 107006 (2008).
Yildirim, T. Origin of the 150-K anomaly in LaFeAsO: Competing antiferromagnetic interactions, frustration, and a structural phase transition. Phys. Rev. Lett. 101, 057010 (2008).
Ma, F. & Lu, Z-Y. Iron-based layered compound LaFeAsO is an antiferromagnetic semimetal. Phys. Rev. B 78, 033111 (2008).
Luetkens, H. et al. The electronic phase diagram of the LaO1−xFxFeAs superconductor. Nature Mater. 8, 305–309 (2009).
Matsuishi, S. et al. Structural analysis and superconductivity of CeFeAsO1−xHx . Phys. Rev. B 85, 014514 (2012).
Rodriguez-Carvajal, J. Recent advances in magnetic structure determination by neutron powder diffraction. Physica B 192, 55–69 (1993).
De la Cruz, C. et al. Magnetic order close to superconductivity in the iron-based layered LaO1−xFxFeAs systems. Nature 453, 899–902 (2008).
Qureshi, N. et al. Crystal and magnetic structure of the oxypnictide superconductor LaFeAsO1−xFx: A neutron-diffraction study. Phys. Rev. B 82, 184521 (2010).
Huang, Q. et al. Neutron-diffraction measurements of magnetic order and a structural transition in the parent BaFe2As2 compound of FeAs-based high-temperature superconductors. Phys. Rev. Lett. 101, 257003 (2008).
Lumsden, M. D. & Christianson, A. D. Magnetism in Fe-based superconductors. J. Phys. Condens. Matter 22, 203203 (2010).
Klauss, H-H. et al. Commensurate spin density wave in LaFeAsO: A local probe study. Phys. Rev. Lett. 101, 077005 (2008).
Uemura, Y. J. Superconductivity: Commonalities in phase and mode. Nature Mater. 8, 253–255 (2009).
Takeshita, S. et al. Insular superconductivity in a Co-doped iron pnictide CaFe1−xCoxAsF. Phys. Rev. Lett. 103, 027002 (2009).
Izumi, F. & Momma, K. Three-dimensional visualization in powder diffraction. Solid State Phenom. 130, 15–20 (2007).
Lee, C-C., Yin, W-G. & Ku, W. Ferro-orbital order and strong magnetic anisotropy in the parent compounds of iron-pnictide superconductors. Phys. Rev. Lett. 103, 267001 (2009).
Lv, W., Wu, J. & Phillips., P. Orbital ordering induces structural phase transition and the resistivity anomaly in iron pnictides. Phys. Rev. B 80, 224506 (2009).
de’ Medici, L., Hassan, S. R., Capone, M. & Dai, X. Orbital-selective Mott transition out of band degeneracy lifting. Phys. Rev. Lett. 102, 126401 (2009).
Lanatà, N. et al. Orbital selectivity in Hund’s metals: The iron chalcogenides. Phys. Rev. B 87, 045122 (2013).
Yamakawa, Y. et al. Phase diagram and superconducting states in LaFeAsO1−xHx based on the multiorbital extended Hubbard model. Phys. Rev. B 88, 041106(R) (2013).
Acknowledgements
We thank K. Yamada for helpful discussions. The neutron, muon and synchrotron radiation experiments were performed at J-PARC (BL08-SuperHRPD, BL21-NOVA, Muon D1), PSI, KEK-PF (BL-8A/8B), and SPring-8 with the approval of JASRI (BL11XU) (Proposal Nos. 2013S2-002, 2009S05, 2013A3502). This work was supported by MEXT Elements Strategy Initiative to Form Core Research Center.
Author information
Authors and Affiliations
Contributions
Y.M., R. Kadono, S.I., S.M. and H. Hosono conceived the study. M.H., K.K., M.M., I.Y., A.K. and R. Kadono carried out the muon experiment. S.I. synthesized the samples. J.Y. and R. Kumai measured the synchrotron X-ray diffraction. H. Hiraka, J.Y., K. Ikeda, P.M., Y.I., S.T., T.K. and T.O. performed the neutron scattering experiments. J.Y., M.Y. and K. Ishii measured the X-ray absorption. M.H., K.K., J.Y. and H. Hiraka co-wrote the manuscript. All the authors discussed the results and the manuscript.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing financial interests.
Supplementary information
Supplementary Information
Supplementary Information (PDF 731 kb)
Rights and permissions
About this article
Cite this article
Hiraishi, M., Iimura, S., Kojima, K. et al. Bipartite magnetic parent phases in the iron oxypnictide superconductor. Nature Phys 10, 300–303 (2014). https://doi.org/10.1038/nphys2906
Received:
Accepted:
Published:
Issue date:
DOI: https://doi.org/10.1038/nphys2906
This article is cited by
-
Electrical Resistivity and Magnetization Study on LaFe2As2, La0.8Ba0.2Fe2As2, and La1-xBaxPt0.1Fe1.9As2 (x = 0, 0.05, 0.2, 0.4, and 0.6) Superconducting Compounds
Journal of Electronic Materials (2022)
-
Co-doping effects on magnetism and superconductivity in the 112-type EuFeAs2 system
Science China Physics, Mechanics & Astronomy (2021)
-
Iron-based superconductors: tales from the nuclei
La Rivista del Nuovo Cimento (2020)
-
Structural phase transition, antiferromagnetism and two superconducting domes in LaFeAsO1-xFx (0 < x ≤ 0.75)
Science China Physics, Mechanics & Astronomy (2018)
-
Observation of two superconducting domes under pressure in tetragonal FeS
npj Quantum Materials (2017)
