Theory of Electron Correlation and Disorder in CrSb Altermagnet

Motivated by the altermagnet order reported for CrSb and evidence of electron correlations in this compound, we address the role of dynamical Coulomb interactions on its hexagonal Dirac fermion regime. We find that a Dirac-to-Fermi liquid crossover develops near half-filling upon increasing electron correlations and identify strong spin selectivity when the system is at the physical electron count. The selectivity is manifested in the formation of spin-resolved Hubbard bands, with clear local moments in the majority spin sector. These features lead to a strong renormalization of the electronic structure while reducing the spin-splitting. We also report on the electronic changes induced by site-diagonal disorder, revealing the nature of the reshaped Dirac and Hubbard lineshapes at low and high energies, respectively. Our results provide a basis to understand the implications of altermaganetism on the current-voltage characteristic of normal and disordered CrSb.