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arXiv · 1904.01930

Spin waves and spin-state transitions in a ruthenate high-temperature antiferromagnet

H. Suzuki·H. Gretarsson·H. Ishikawa·K. Ueda·Z. Yang·H. Liu·H. Kim·D. Kukusta·A. Yaresko·M. Minola·J. A. Sears·S. Francoual·H. -C. Wille·J. Nuss·H. Takagi·B. J. Kim·G. Khaliullin·H. Yavas·B. Keimer
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Abstract

Ruthenium compounds play prominent roles in materials research ranging from oxide electronics to catalysis, and serve as a platform for fundamental concepts such as spin-triplet superconductivity, Kitaev spin-liquids, and solid-state analogues of the Higgs mode in particle physics. However, basic questions about the electronic structure of ruthenates remain unanswered, because several key parameters (including the Hund's-rule, spin-orbit, and exchange interactions) are comparable in magnitude, and their interplay is poorly understood - partly due to difficulties in synthesizing sizable single crystals for spectroscopic experiments. Here we introduce a resonant inelastic x-ray scattering (RIXS) technique capable of probing collective modes in microcrystals of $4d$-electron materials. We present a comprehensive set of data on spin waves and spin-state transitions in the honeycomb antiferromagnet SrRu$_{2}$O$_{6}$, which possesses an unusually high N\'eel temperature. The new RIXS method provides fresh insight into the unconventional magnetism of SrRu$_{2}$O$_{6}$, and enables momentum-resolved spectroscopy of a large class of $4d$ transition-metal compounds.

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H. Suzuki, H. Gretarsson, H. Ishikawa, K. Ueda, Z. Yang, H. Liu, H. Kim, D. Kukusta, A. Yaresko, M. Minola, J. A. Sears, S. Francoual, H. -C. Wille, J. Nuss, H. Takagi, B. J. Kim, G. Khaliullin, H. Yavas, B. Keimer. 2019-04-03. Spin waves and spin-state transitions in a ruthenate high-temperature antiferromagnet. https://doi.org/10.1038/s41563-019-0327-2

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