Nanoscale phase separation of antiferromagnetic order and superconductivity in K0.75Fe1.75Se2
Open Access
- 12 January 2012
- journal article
- research article
- Published by Springer Science and Business Media LLC in Scientific Reports
- Vol. 2 (1), 221
- https://doi.org/10.1038/srep00221
Abstract
We report an in-plane optical spectroscopy study on the iron-selenide superconductor K0.75Fe1.75Se2. The measurement revealed the development of a sharp reflectance edge below Tc at frequency much smaller than the superconducting energy gap on a relatively incoherent electronic background, a phenomenon which was not seen in any other Fe-based superconductors so far investigated. Furthermore, the feature could be noticeably suppressed and shifted to lower frequency by a moderate magnetic field. Our analysis indicates that this edge structure arises from the development of a Josephson-coupling plasmon in the superconducting condensate. Together with the transmission electron microscopy analysis, our study yields compelling evidence for the presence of nanoscale phase separation between superconductivity and magnetism. The results also enable us to understand various seemingly controversial experimental data probed from different techniques.Other Versions
This publication has 26 references indexed in Scilit:
- Electronic and magnetic structures of the ternary iron selenides AFe2Se2 (A=Cs, Rb, K, or Tl)Physical Review B, 2011
- Absence of a Holelike Fermi Surface for the Iron-BasedSuperconductor Revealed by Angle-Resolved Photoemission SpectroscopyPhysical Review Letters, 2011
- Electronic structure, topological phase transitions and superconductivity in (K, Cs) x Fe2Se2JETP Letters, 2011
- Fe-based superconductivity with T c =31 K bordering an antiferromagnetic insulator in (Tl,K) Fe x Se 2Europhysics Letters, 2011
- Coexistence of Magnetism and Superconductivity in the Iron-Based CompoundPhysical Review Letters, 2011
- Nodeless superconducting gap in AxFe2Se2 (A=K,Cs) revealed by angle-resolved photoemission spectroscopyNature Materials, 2011
- Superconductivity in the iron selenidePhysical Review B, 2010
- Electronic structure of Fe-based superconductorsPhysica C: Superconductivity and its Applications, 2009
- Competing orders and spin-density-wave instability in La(O 1−x F x )FeAsEurophysics Letters, 2008
- Magnetic order close to superconductivity in the iron-based layered LaO1-xF x FeAs systemsNature, 2008