Powder inelastic neutron scattering of a spin-liquid candidate Ba₃ZnRu₂O₉

Ba₃ZnRu₂O₉ (BZRO) is a 6-H perovskite compound that contains triangular lattice layers of Ru⁵⁺ dimers, and was recently reported to have no signatures of long-range-magnetic-order down to 37 mK and therefore put forward as a spin-liquid candidate.[1] We present inelastic neutron scattering measurements on BZRO powder that show a magnetic feature with a momentum dependence that is similar to the Ru-magnetic-form-factor, a peak energy intensity at 25 meV, and no obvious dispersive character. This magnetic mode is then considered in the context of density functional theory calculations and magnetization measurements. Comparisons are then made to the historical work on the analogous Ba₃CaRu₂O₉.[2]

[1] I. Terasaki, and co-authors, J. Phys. Soc. Jpn. 86, 033702 (2017) [4 Pages]
[2] J. Darriet, and co-authors, J. Phys. Chem. Solids 44 (1983) pp. 269-212.