Quantitative comparison of LDA + DMFT and ARPES spectral functions

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 lifetime of the photo-hole arising in the process of photoemission. In this article, we present a robust procedure for taking into account these experimental features by the example of iron-based high-temperature superconductors systems: NaFeAs and FeSe on a SrTiO$_3$ substrate.