Comparison of Ab initio Low-Energy Models for LaFePO, LaFeAsO, BaFe2As2, LiFeAs, FeSe and FeTe: Electron Correlation and Covalency

Takashi Miyake; Kazuma Nakamura; Ryotaro Arita; Masatoshi Imada

doi:10.1143/jpsj.79.044705

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arXiv · 0911.3705

Comparison of Ab initio Low-Energy Models for LaFePO, LaFeAsO, BaFe2As2, LiFeAs, FeSe and FeTe: Electron Correlation and Covalency

Takashi Miyake·Kazuma Nakamura·Ryotaro Arita·Masatoshi Imada

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Abstract

Effective low-energy Hamiltonians for several different families of iron-based superconductors are compared after deriving them from the downfolding scheme based on first-principles calculations. Systematic dependences of the derived model parameters on the families are elucidated, many of which are understood from the systematic variation of the covalency between Fe-3d and pnictogen-/chalcogen-p orbitals.

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Takashi Miyake, Kazuma Nakamura, Ryotaro Arita, Masatoshi Imada. 2010-03-09. Comparison of Ab initio Low-Energy Models for LaFePO, LaFeAsO, BaFe2As2, LiFeAs, FeSe and FeTe: Electron Correlation and Covalency. https://doi.org/10.1143/jpsj.79.044705

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