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arXiv · 1505.04963

Electronic structure of NaFeAs superconductor: LDA+DMFT calculations compared with ARPES experiment

I. A. Nekrasov·N. S. Pavlov·M. V. Sadovskii
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Abstract

We present the results of extended theoretical LDA+DMFT calculations for a new iron-pnictide high temperature superconductor NaFeAs compared with the recent high quality angle-resolved photoemission (ARPES) experiments on this system [1]. The universal manifestation of correlation effects in iron-pnictides is narrowing of conducting bands near the Fermi level. Our calculations demonstrate that for NaFeAs the effective mass is renormalized on average by a factor of the order of 3, in good agreement with ARPES data. This is essentially due to correlation effects on Fe-3d orbitals only and no additional interactions with with any kind of Boson modes, as suggested in [1], are necessary to describe the experiment. Also we show that ARPES data taken at about 160 eV beam energy most probably corresponds to $k_z=\pi$ Brillouin zone boundary, while ARPES data measured at about 80 eV beam energy rather represents $k_z=0$. Contributions of different Fe-3d orbitals into spectral function map are also discussed.

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I. A. Nekrasov, N. S. Pavlov, M. V. Sadovskii. 2015-05-19. Electronic structure of NaFeAs superconductor: LDA+DMFT calculations compared with ARPES experiment. https://doi.org/10.1134/s0021364015130123

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