Orbital dichotomy of Fermi liquid properties in Sr2RuO4 revealed by Raman spectroscopy
Abstract
We report a polarization-resolved Raman spectroscopy study of the orbital dependence of the quasiparticles properties in the prototypical multi-band Fermi liquid Sr2RuO4. We show that the quasiparticle scattering rate displays ω2 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 dxz/yz orbital derived quasiparticles showing significantly more robust Fermi liquid properties than the dxy orbital derived ones. The observed orbital dichotomy of the quasiparticles is consistent with the picture of Sr2RuO4 as a Hund's metal. Our study establishes Raman scattering as a powerful probe of Fermi liquid properties in correlated metals.