Journal Article

FZJ-2023-02082

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Spin fluctuations in Sr 1.8 La 0.2 RuO 4

He, Z. ; Wang, Q. (Corresponding author) ; Feng, Y. ; Kim, C. ; Kyung, W. ; Kim, C. ; Wo, H. ; Ding, G. ; Hao, Y. ; Liu, F. ; Walker, H. C. ; Adroja, D. T. ; Schneidewind, A.FZJ* ; Wang, W. ; Zhao, J. (Corresponding author)

2023
Inst. Woodbury, NY

This record in other databases:    

Please use a persistent id in citations: http://hdl.handle.net/2128/34508  doi:10.1103/PhysRevB.107.L201107

Abstract: We use inelastic neutron scattering to study spin fluctuations in Sr1.8La0.2RuO4, where Lanthanum doping triggers a Lifshitz transition by pushing the van Hove singularity in the γ band to the Fermi energy. Strong spinfluctuations emerge at an incommensurate wave vector Qic = (0.3, 0.3), corresponding to the nesting vector between α and β Fermi sheets. The incommensurate antiferromagnetic fluctuations shift toward (0.25,0.25) with increasing energy up to ∼110 meV. By contrast, scatterings near the ferromagnetic wave vectors Q = (1, 0) and (1,1) remain featureless at all energies. This contradicts the weak-coupling perspective that suggests a sharpenhancement of ferromagnetic susceptibility due to the divergence of density of states in the associated γ band. Our findings imply that ferromagnetic fluctuations in Sr2RuO4 and related materials do not fit into the weakcoupling paradigm, but instead are quasilocal fluctuations induced by Hund’s coupling. This imposes significant constraints for the pairing mechanism involving spin fluctuations.

Keyword(s): Magnetic Materials (1st) ; Condensed Matter Physics (2nd) ; Magnetism (2nd)

---

Contributing Institute(s):

1. JCNS-FRM-II (JCNS-FRM-II)
2. Heinz Maier-Leibnitz Zentrum (MLZ)
3. Streumethoden (JCNS-2)
4. JCNS-4 (JCNS-4)

Research Program(s):

1. 6G4 - Jülich Centre for Neutron Research (JCNS) (FZJ) (POF4-6G4) (POF4-6G4)
2. 632 - Materials – Quantum, Complex and Functional Materials (POF4-632) (POF4-632)

Experiment(s):

1. PANDA: Cold three axes spectrometer (SR2)

Appears in the scientific report 2023

---

Database coverage:
; ; ; Clarivate Analytics Master Journal List ; Current Contents - Electronics and Telecommunications Collection ; Current Contents - Physical, Chemical and Earth Sciences ; Ebsco Academic Search ; Essential Science Indicators ; IF < 5 ; JCR ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

---