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arXiv · 1105.3352

Inelastic neutron scattering study of the magnetic fluctuations in Sr$_2$RuO$_4$

K. Iida·M. Kofu·N. Katayama·J. Lee·R. Kajimoto·Y. Inamura·M. Nakamura·M. Arai·Y. Yoshida·M. Fujita·K. Yamada·S. -H. Lee
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Abstract

By performing time-of-flight neutron scattering measurements on a large amount of single crystals of Sr$_2$RuO$_4$, we studied detailed structure of the imaginary part of the dynamic spin susceptibility over a wide range of phase space. In the normal state at T=5 K, strong incommensurate (IC) peaks were clearly observed at around $\mathbf{Q}_\text{c}=(0.3,0.3)$ up to at least $\hbarω=80$ meV. In addition, our data also show strong magnetic fluctuations that exist on the ridges connecting the IC peaks around the $(π,π)$ point rather than around the $Γ$ point. Our results are consistent with the semi-mean-field random phase approximation calculation for a two dimensional Fermi liquid with a characteristic energy of 5.0 meV. Furthermore, the IC fluctuations were observed even at room temperature.

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K. Iida, M. Kofu, N. Katayama, J. Lee, R. Kajimoto, Y. Inamura, M. Nakamura, M. Arai, Y. Yoshida, M. Fujita, K. Yamada, S. -H. Lee. 2011-05-17. Inelastic neutron scattering study of the magnetic fluctuations in Sr$_2$RuO$_4$. https://doi.org/10.1103/physrevb.84.060402

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