Fig. 3: Element specific quasiparticle lifetimes (τ) and frequency resolved optical conductivity of the CrMnFeCoNi HEA.
From: Interplay between disorder and electronic correlations in compositionally complex alloys
a τ from LDA + DMFT calculations for Fe and Ni. Top: Black lines show calculated τ for pure elements in their natural crystal structures; yellow lines show τ for pure metals within the fcc structure and CrMnFeCoNi lattice constant (γ-Fe). Experimental values are from photoemission spectroscopy (PES, below EF)43 and time-resolved two-photon photoemission (TR-2PPE, above EF)44,45,46 of pure elements. Ni shows negligible variation, while γ-Fe exhibits notably reduced lifetimes. Bottom: Blue lines correspond to the CrMnFeCoNi HEA results. Green lines show results with increased U for Fe and Ni (2 eV and 4 eV, respectively). Increasing U reduces τ, particularly for Ni at E > EF. b Real (Re(σ)) and imaginary (Im(σ)) parts of the complex optical conductivity (σ) versus photon energy (ℏω). LDA calculations are shown as yellow lines, and LDA + DMFT calculations as blue lines. Experimental data from reflectometry (Exp. 1) and ellipsometry (Exp. 2) are given by black lines and marked by arrows. LDA + DMFT results show better agreement with experimental data, especially in the visible and UV ranges, for both Re(σ) and Im(σ).
