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arXiv · 1112.4682

Ab initio Evidence for Strong Correlation Associated with Mott Proximity in Iron-based Superconductors

Takahiro Misawa·Kazuma Nakamura·Masatoshi Imada
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Abstract

We predict that iron-based superconductors discovered near d6 configuration (5 Fe 3d orbitals filled by 6 electrons) is located on the foot of an unexpectedly large dome of correlated electron matter centered at the Mott insulator at d5 (namely, half filling). This is based on the many-variable variational Monte-Carlo results for ab initio low-energy models derived by the downfolding. The d5 Mott proximity extends to subsequent emergence of incoherent metals, orbital differentiations due to the Mott physics and Hund's-rule coupling, followed by antiferromagnetic quantum criticality, in quantitative accordance with available experiments.

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Takahiro Misawa, Kazuma Nakamura, Masatoshi Imada. 2011-12-20. Ab initio Evidence for Strong Correlation Associated with Mott Proximity in Iron-based Superconductors. https://doi.org/10.1103/physrevlett.108.177007

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