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تسجيل مستخدم جديدTetragonal and collapsed-tetragonal phases of CaFe2As2 -- a view from angle-resolved photoemission and dynamical mean field theory
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We present a study of the tetragonal to collapsed-tetragonal transition of CaFe2As2 using angle-resolved photoemission experiments and dynamical mean field theory-based electronic structure calculations. We observe that the collapsed-tetragonal phase exhibits reduced correlations and a higher coherence temperature due to the stronger Fe-As hybridization. Furthermore, a comparison of measured photoemission spectra and theoretical spectral functions shows that momentum-dependent corrections to the density functional band structure are essential for the description of low-energy quasiparticle dispersions. We introduce those using the recently proposed combined Screened Exchange + Dynamical Mean Field Theory scheme.
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