Fractional power-law behavior and its origin in iron-chalcogenide and ruthenate superconductors: Insights from first-principles calculations

Article

关键词: MEAN-FIELD THEORY;    INFINITE DIMENSIONS;    METALS;    PNICTIDES;    SR2RUO4;    STATES;   

DOI  :  10.1103/PhysRevB.86.195141

来源: SCIE

【 摘 要 】

We perform realistic first-principles calculations of iron chalcogenides and ruthenate-based materials to identify experimental signatures of Hund's-coupling-induced correlations in these systems. We find that FeTe and KxFe2-yAs2 display unusual orbital-dependent fractional power-law behavior in their quasiparticle self-energy and optical conductivity, a phenomenon first identified in SrRuO3. Strong incoherence in the paramagnetic state of these materials results in electronic states hidden to angle-resolved photoemission spectroscopy which reemerge at low temperatures. We identify the effective low-energy Hamiltonian describing these systems and show that these anomalies are not controlled by the proximity to a quantum critical point but result from coexistence of fast quantum mechanical orbital fluctuations and slow spin fluctuations.

【 授权许可】

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