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تسجيل مستخدم جديدOrbital Selectivity in Hunds metals: The Iron Chalcogenides
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We show that electron correlations lead to a bad metallic state in chalcogenides FeSe and FeTe despite the intermediate value of the Hubbard repulsion $U$ and Hunds rule coupling $J$. The evolution of the quasi particle weight $Z$ as a function of the interaction terms reveals a clear crossover at $U simeq$ 2.5 eV. In the weak coupling limit $Z$ decreases for all correlated $d$ orbitals as a function of $U$ and beyond the crossover coupling they become weakly dependent on $U$ while strongly depend on $J$. A marked orbital dependence of the $Z$s emerges even if in general the orbital-selective Mott transition only occurs for relatively large values of $U$. This two-stage reduction of the quasi particle coherence due to the combined effect of Hubbard $U$ and the Hunds $J$, suggests that the iron-based superconductors can be referred to as Hunds correlated metals.
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