Vacancies, disorder-induced smearing of the electronic structure, and its implications for the superconductivity of anti-perovskite MgC0.93Ni2.85.
- Ernsting D H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS8 1TL, United Kingdom.
- Billington D Japan Synchrotron Radiation Research Institute, SPring-8, Sayo, 679-5198, Japan.
- Millichamp TE H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS8 1TL, United Kingdom.
- Edwards RA H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS8 1TL, United Kingdom.
- Sparkes HA School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, United Kingdom.
- Zhigadlo ND Department of Chemistry and Biochemistry, Freiestrasse 3, University of Bern, Bern, Switzerland.
- Giblin SR School of Physics and Astronomy, Cardiff University, Queen's Building, The Parade, Cardiff, CF24 3AA, United Kingdom.
- Taylor JW DMSC - European Spallation Source, Universitetsparken 1, Copenhagen, 2100, Denmark.
- Duffy JA Department of Physics, University of Warwick, Coventry, CV4 7AL, United Kingdom.
- Dugdale SB H.H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol, BS8 1TL, United Kingdom. s.b.dugdale@bristol.ac.uk.
- 2017-09-02
Published in:
- Scientific reports. - 2017
English
The anti-perovskite superconductor MgC0.93Ni2.85 was studied using high-resolution x-ray Compton scattering combined with electronic structure calculations. Compton scattering measurements were used to determine experimentally a Fermi surface that showed good agreement with that of our supercell calculations, establishing the presence of the predicted hole and electron Fermi surface sheets. Our calculations indicate that the Fermi surface is smeared by the disorder due to the presence of vacancies on the C and Ni sites, but does not drastically change shape. The 20% reduction in the Fermi level density-of-states would lead to a significant (~70%) suppression of the superconducting T c for pair-forming electron-phonon coupling. However, we ascribe the observed much smaller T c reduction at our composition (compared to the stoichiometric compound) to the suppression of pair-breaking spin fluctuations.
- Language
-
- English
- Open access status
- gold
- Identifiers
-
- DOI 10.1038/s41598-017-09997-2
- PMID 28860522
- Persistent URL
- https://sonar.ch/global/documents/241797
Statistics
Document views: 34
File downloads:
- Full-text: 0