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arXiv · 1411.5180

QSGW+DMFT: an electronic structure scheme for the iron pnictides and beyond

Jan M. Tomczak
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Abstract

While in strongly correlated materials one often focuses on local electronic correlations, the influence of non-local exchange and correlation effects beyond band-theory can be pertinent in systems with more extended orbitals. Thus in many compounds an adequate theoretical description requires the joint treatment of local and non-local self-energies. Here, I will argue that this is the case for the iron pnictide and chalcogenide superconductors. As an approach to tackle their electronic structure, I will detail the implementation of the recently proposed scheme that combines the quasi-particle self-consistent GW approach with dynamical mean-field theory: QSGW+DMFT. I will showcase the possibilities of QSGW+DMFT with an application on BaFe2As2. Further, I will discuss the empirical finding that in pnictides dynamical and non-local correlation effects separate within the quasi-particle band-width.

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Jan M. Tomczak. 2014-11-19. QSGW+DMFT: an electronic structure scheme for the iron pnictides and beyond. https://doi.org/10.1088/1742-6596%2F592%2F1%2F012055

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