Orbital selectivity in Hund's metals: The iron chalcogenides
Orbital selectivity in Hund's metals: The iron chalcogenides
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DOI：
10.1103/physrevb.87.045122
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发表时间：
2012-11
影响因子：
3.7
通讯作者：
N. Lanata;H. U. R. Strand;G. Giovannetti;B. Hellsing;L. D. Medici;M. Capone
中科院分区：
文献类型：
--
作者：
N. Lanata;H. U. R. Strand;G. Giovannetti;B. Hellsing;L. D. Medici;M. Capone
我们发现，电子关联导致一个坏的金属状态的硫属化物FeSe和FeTe，尽管中间值的哈伯德排斥U和洪德规则耦合J。准粒子重量Z作为相互作用项的函数的演化揭示了在U = 2.5 eV处的明显交叉。在弱耦合极限下，所有相关d轨道的Z都随U的变化而减小，在交叉耦合极限之外，它们对U的依赖性变弱，而对J的依赖性变强。一个显着的轨道依赖的Z的出现，即使在一般情况下，轨道选择性莫特跃迁只发生在相对较大的值的U。由于Hubbard U和Hund's J的联合作用，准粒子相干性的这种两阶段减少表明铁基超导体可以被称为Hund's关联金属。
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 Hund’s rule coupling J . The evolution of the quasiparticle weight Z as a function of the interaction terms reveals a clear crossover at U � 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 dependent 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 quasiparticle coherence due to the combined effect of Hubbard U and the Hund’s J suggests that the iron-based superconductors can be referred to as Hund’s correlated metals.