%0 Journal Article
%A Bertinshaw, J.
%A Krautloher, Maximilian
%A Suzuki, H.
%A Takahashi, Hiroto
%A Ivanov, A.
%A Yavaş, H.
%A Kim, Bumjoon
%A Gretarsson, H.
%A Keimer, B.
%T Spin and charge excitations in the correlated multiband metal Ca<sub>3</sub>Ru<sub>2</sub>O<sub>7</sub>
%J Physical review / B
%V 103
%N 8
%@ 2469-9950
%C Woodbury, NY
%I Inst.
%M PUBDB-2021-00998
%P 085108
%D 2021
%X We use Ru L<sub>3</sub>-edge resonant inelastic x-ray scattering to study the full range of excitations in Ca<sub>3</sub>Ru<sub>2</sub>O<sub>7</sub> from meV-scale magnetic dynamics through to the eV-scale interband transitions. This bilayer 4d-electron correlated metal expresses a rich phase diagram, displaying long-range magnetic order below 56 K followed by a concomitant structural, magnetic, and electronic transition at 48 K. In the low-temperature phase, we observe a magnetic excitation with a bandwidth of ∼30 meV and a gap of ∼8 meV at the zone center, in excellent agreement with inelastic neutron scattering data. The dispersion can be modeled using a Heisenberg Hamiltonian for a bilayer S=1 system with single-ion anisotropy terms. At a higher energy loss, dd-type excitations show heavy damping in the presence of itinerant electrons, giving rise to a fluorescencelike signal appearing between the t<sub>2g</sub> and e<sub>g</sub> bands. At the same time, we observe a resonance originating from localized t<sub>2g</sub> excitations, in analogy to the structurally related Mott insulator Ca<sub>2</sub>RuO<sub>4</sub>. But whereas Ca<sub>2</sub>RuO<sub>4</sub> shows sharp separate spin-orbit excitations and Hund's-rule driven spin-state transitions, here we identify only a single broad asymmetric feature. These results indicate that local intraionic interactions underlie the correlated physics in Ca<sub>3</sub>Ru<sub>2</sub>O<sub>7</sub>, even as the excitations become strongly mixed in the presence of itinerant electrons. 
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000615717100002
%R 10.1103/PhysRevB.103.085108
%U https://bib-pubdb1.desy.de/record/455234