Observation of a neutron spin resonance in the bilayered superconductor CsCa2Fe4As4F2.
J Phys Condens Matter
; 32(43): 435603, 2020 Aug 05.
Article
in En
| MEDLINE
| ID: mdl-32756017
ABSTRACT
We report inelastic neutron scattering (INS) investigations on the bilayer Fe-based superconductor CsCa2Fe4As4F2 above and below its superconducting transition temperature T c ≈ 28.9 K to investigate the presence of a neutron spin resonance. This compound crystallises in a body-centred tetragonal lattice containing asymmetric double layers of Fe2As2 separated by insulating CaF2 layers and is known to be highly anisotropic. Our INS study clearly reveals the presence of a neutron spin resonance that exhibits higher intensity at lower momentum transfer (Q) at 5 K compared to 54 K, at an energy of 15 meV. The energy E R of the observed spin resonance is broadly consistent with the relationship E R = 4.9k B T c, but is slightly enhanced compared to the values observed in other Fe-based superconductors. We discuss the nature of the electron pairing symmetry by comparing the value of E R with that deduced from the total superconducting gap value integrated over the Fermi surface.
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1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
J Phys Condens Matter
Journal subject:
BIOFISICA
Year:
2020
Document type:
Article
Affiliation country: