TY  - JOUR
AU  - He, Zheng
AU  - Wang, Qisi
AU  - Feng, Yu
AU  - Kim, Chul
AU  - Kyung, Wonshik
AU  - Kim, Changyoung
AU  - Wo, Hongliang
AU  - Ding, Gaofeng
AU  - Hao, Yiqing
AU  - Liu, Feiyang
AU  - Walker, Helen C.
AU  - Adroja, Devashibhai T.
AU  - Schneidewind, Astrid
AU  - Wang, Wenbin
AU  - Zhao, Jun
TI  - Spin fluctuations in Sr 1.8 La 0.2 RuO 4
JO  - Physical review / B
VL  - 107
IS  - 20
SN  - 2469-9950
CY  - Woodbury, NY
PB  - Inst.
M1  - FZJ-2023-02082
SP  - L201107
PY  - 2023
AB  - 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.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000993596700003
DO  - DOI:10.1103/PhysRevB.107.L201107
UR  - https://juser.fz-juelich.de/record/1007492
ER  -