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تسجيل مستخدم جديدOrbitally selective breakdown of Fermi liquid quasiparticles in Ca$_{1.8}$Sr$_{0.2}$RuO$_4$
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We present a comprehensive angle-resolved photoemission spectroscopy study of Ca$_{1.8}$Sr$_{0.2}$RuO$_4$. Four distinct bands are revealed and along the Ru-O bond direction their orbital characters are identified through a light polarization analysis and comparison to dynamical mean-field theory calculations. Bands assigned to $d_{xz}, d_{yz}$ orbitals display Fermi liquid behavior with fourfold quasiparticle mass renormalization. Extremely heavy fermions - associated with a predominantly $d_{xy}$ band character - are shown to display non-Fermi-liquid behavior. We thus demonstrate that Ca$_{1.8}$Sr$_{0.2}$RuO$_4$ is a hybrid metal with an orbitally selective Fermi liquid quasiparticle breakdown.
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