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arXiv · 2103.16698

Orbital dichotomy of Fermi liquid properties in Sr$_2$RuO$_4$ revealed by Raman spectroscopy

J. -C. Philippe·B. Baptiste·C. Sow·Y. Maeno·A. Forget·D. Colson·M. Cazayous·A. Sacuto·Y. Gallais
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Abstract

We report a polarization-resolved Raman spectroscopy study of the orbital dependence of the quasiparticles properties in the prototypical multi-band Fermi liquid Sr\textsubscript{2}RuO\textsubscript{4}. We show that the quasiparticle scattering rate displays $\omega^{2}$ dependence as expected for a Fermi liquid. Besides, we observe a clear polarization-dependence in the energy and temperature dependence of the quasiparticle scattering rate and mass, with the $d_{xz/yz}$ orbital derived quasiparticles showing significantly more robust Fermi liquid properties than the $d_{xy}$ orbital derived ones. The observed orbital dichotomy of the quasiparticles is consistent with the picture of Sr\textsubscript{2}RuO\textsubscript{4} as a Hund's metal. Our study establishes Raman scattering as a powerful probe of Fermi liquid properties in correlated metals.

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J. -C. Philippe, B. Baptiste, C. Sow, Y. Maeno, A. Forget, D. Colson, M. Cazayous, A. Sacuto, Y. Gallais. 2021-03-30. Orbital dichotomy of Fermi liquid properties in Sr$_2$RuO$_4$ revealed by Raman spectroscopy. https://doi.org/10.1103/physrevb.103.235147

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