Effect of Fermi surface nesting on resonant spin excitations in Ba{<_1-x}K{<_x}Fe{<_2}As{<_2}.

Journal Article · Sat Jan 01 04:00:00 EST 2011 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.107.177003· OSTI ID:1028615

Castellan, J -P; Rosenkranz, S; Goremychkin, E A; Chung, D Y; Todorov, I S; Kanatzidis, M G; Eremin, I; Knolle, J; Chubukov, A V; Maiti, s; Norman, M R; Weber, F; Claus, H; Guidi, T; Bewley, R I; Osborn, R ^[1]

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1. Materials Science Division

We report inelastic neutron scattering measurements of the resonant spin excitations in Ba{sub 1-x}K{sub x}Fe{sub 2}As{sub 2} over a broad range of electron band filling. The fall in the superconducting transition temperature with hole doping coincides with the magnetic excitations splitting into two incommensurate peaks because of the growing mismatch in the hole and electron Fermi surface volumes, as confirmed by a tight-binding model with s{sub {+-}}-symmetry pairing. The reduction in Fermi surface nesting is accompanied by a collapse of the resonance binding energy and its spectral weight, caused by the weakening of electron-electron correlations.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: SC
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1028615
• Report Number(s): ANL/MSD/JA-70828
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 17 Vol. 107; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARIUM COMPOUNDS
BINDING ENERGY
CORRELATIONS
ELECTRONS
FERMI LEVEL
HOLES
INELASTIC SCATTERING
IRON ARSENIDES
NEUTRONS
POTASSIUM COMPOUNDS
REDUCTION
RESONANCE
SPIN
SUPERCONDUCTIVITY
SYMMETRY
TRANSITION TEMPERATURE
WEIGHT