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arXiv · 2103.08161

Quantitative comparison of LDA+DMFT and ARPES spectral functions

I. A. Nekrasov·N. S. Pavlov
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Abstract

The emergence of angle-resolved photoemission spectroscopy (ARPES) made it possible to observe electronic dispersion directly as a spectral function map. On the other hand, a spectral function map can be obtained theoretically, for example, in the LDA+DMFT method. The electronic band on such a map is characterized not only by its energy position at a given $k$-point, but also by its width and intensity. To illustrate a way of quantitative comparison of theoretical spectral functions and ARPES data, spectral functions obtained by the LDA+DMFT method are chosen. It is shown that the theoretical spectral functions should take into account a number of experimental features: the photoionization cross section, the experimental energy and angular resolution, as well as the effects of the photohole lifetime arising in the process of photoemission. In this article, we present a robust procedure for taking these experimental features into account by the example of iron-based high-temperature superconductors (HTSC) systems: NaFeAs and FeSe on a SrTiO$_3$ substrate.

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I. A. Nekrasov, N. S. Pavlov. 2021-03-15. Quantitative comparison of LDA+DMFT and ARPES spectral functions. https://doi.org/10.1134/s0021364021020089

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