Structural and magnetic phase diagram of CeFeAsO1- xFx and its relation to high-temperature superconductivity
Abstract
Recently, high-transition-temperature (high-Tc) superconductivity was discovered in the iron pnictide RFeAsO1-xFx (R, rare-earth metal) family of materials. We use neutron scattering to study the structural and magnetic phase transitions in CeFeAsO1-xFx as the system is tuned from a semimetal to a high-Tc superconductor through fluorine (F) doping, x. In the undoped state, CeFeAsO develops a structural lattice distortion followed by a collinear antiferromagnetic order with decreasing temperature. With increasing fluorine doping, the structural phase transition decreases gradually and vanishes within the superconductivity dome near x=0.10, whereas the antiferromagnetic order is suppressed before the appearance of superconductivity for x>0.06, resulting in an electronic phase diagram remarkably similar to that of the high-Tc copper oxides. Comparison of the structural evolution of CeFeAsO1-xFx with other Fe-based superconductors suggests that the structural perfection of the Fe-As tetrahedron is important for the high-Tc superconductivity in these Fe pnictides.
- Publication:
-
Nature Materials
- Pub Date:
- December 2008
- DOI:
- 10.1038/nmat2315
- arXiv:
- arXiv:0806.2528
- Bibcode:
- 2008NatMa...7..953Z
- Keywords:
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- Condensed Matter - Superconductivity;
- Condensed Matter - Strongly Correlated Electrons
- E-Print:
- 19 pages, 5 figures