Phonons of Fe-based superconductor Ca10Pt4As8(Fe1−xPtxAs)10. (28th October 2015)

• Record Type: Journal Article
• Authors: Ikeuchi, K; Kobayashi, Y; Suzuki, K; Itoh, M; Kajimoto, R; Bourges, P; Christianson, A D; Nakamura, H; Machida, M; Sato, M
• Is Part Of: Journal of physics. Volume 27:Number 46(2015)
• Publication Date: 2015-10-28
• Subjects: Fe-based superconductors -- superconducting symmetry -- inelastic neutron scattering; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/0953-8984/27/46/465701
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: We report the results of inelastic neutron scattering measurements on particular phonons of a superconducting (SC) Ca10 Pt4 As8 (Fe1− x Pt x As)10 with the onset transition temperature T c ~ 33 K to investigate mainly what roles orbital fluctuation plays in Cooper pairing, where we observed a slight softening of the in-plane transverse acoustic mode corresponding to the elastic constant C 66 . This softening starts at temperature T well above the SC T c, as T decreases. An anomalously strong change of the scattering intensity of in-plane optical modes was observed at the M point of the pseudo tetragonal reciprocal space in the range of 35 < ω < 40 meV with decreasing T from far above T c . Because this ω region mainly corresponds to the motion of Fe and As atoms in the FeAs planes, the finding presents information on the coupling between the orbital fluctuation of Fe 3 d electrons and the lattice system, useful for studying the possible roles of orbital fluctuation in the pairing mechanism and/or the appearance of the so-called nematic phase.