Electronic Structure of a Correlated Antiferromagnetic Metal CrN in Epitaxial Thin Film Form

Chromium nitride (CrN) is a prototypical correlated antiferromagnet in which magnetic ordering is concomitant with a structural transition in its bulk form, yet its low-energy electronic structure in thin films remains largely unexplored. Here we investigate high-quality epitaxial CrN/MgO (001) thin films using angle-resolved photoemission spectroscopy (ARPES). Transport measurements reveal that the films remain metallic and undergo a magnetic transition without detectable structural distortion. ARPES directly resolves a shallow electron-like band crossing the Fermi level (E_F), forming a small Fermi surface that persists across the Néel temperature (T_N). A pronounced redistribution of spectral weight is observed, which may be related to the magnetic transition. Comparison with first-principles calculations shows that electronic correlations are essential to reproduce the observed band topology, establishing epitaxial CrN as a correlated antiferromagnetic (AFM) metal. These results help understand the interplay between magnetism, correlations, and lattice constraints in CrN, offering an example of tailoring electronic and magnetic properties in correlated AFM thin films.