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Distinct spin and orbital dynamics in Sr₂RuO₄.

ABSTRACT: The unconventional superconductor Sr₂RuO₄ has long served as a benchmark for theories of correlated-electron materials. The determination of the superconducting pairing mechanism requires detailed experimental information on collective bosonic excitations as potential mediators of Cooper pairing. We have used Ru L₃-edge resonant inelastic x-ray scattering to obtain comprehensive maps of the electronic excitations of Sr₂RuO₄ over the entire Brillouin zone. We observe multiple branches of dispersive spin and orbital excitations associated with distinctly different energy scales. The spin and orbital dynamical response functions calculated within the dynamical mean-field theory are in excellent agreement with the experimental data. Our results highlight the Hund metal nature of Sr₂RuO₄ and provide key information for the understanding of its unconventional superconductivity.

SUBMITTER: Suzuki H

PROVIDER: S-EPMC10624926 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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Distinct spin and orbital dynamics in Sr2RuO4.

Suzuki H H Wang L L Bertinshaw J J Strand H U R HUR Käser S S Krautloher M M Yang Z Z Wentzell N N Parcollet O O Jerzembeck F F Kikugawa N N Mackenzie A P AP Georges A A Hansmann P P Gretarsson H H Keimer B B

Nature communications 20231103 1

The unconventional superconductor Sr2RuO4 has long served as a benchmark for theories of correlated-electron materials. The determination of the superconducting pairing mechanism requires detailed experimental information on collective bosonic excitations as potential mediators of Cooper pairing. We have used Ru L3-edge resonant inelastic x-ray scattering to obtain comprehensive maps of the electronic excitations of Sr2RuO4 over the entire B ...[more]

PMID: 37923750

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