Orbital-differentiated correlated state and magnetic compensation in off-stoichiometry Heusler-like compounds
Phys. Rev. B 114, 295107 – Published 6 November, 2026
DOI: https://doi.org/10.1103/qkdw-zm78
Abstract
Off-stoichiometry Heusler-like compounds provide a platform in which fractional site occupation can generate local orbital inequivalence beyond the conventional Slater-Pauling electron-counting picture. Here, we investigate the family using first-principles density functional theory and dynamical mean-field theory (DMFT), and show that mixed 4c/4d occupation creates inequivalent Co- states with distinct orbital fillings, hybridization strengths, and correlation responses. The resulting 4c/4d inequivalence drives a short-range interplay between Co- states, establishing a local orbital configuration that underlies magnetic compensation. Crucially, our DMFT calculations reveal that this compensated state is not a simple uniform band-semiconducting ferrimagnet, but an orbital-differentiated correlated state characterized by a site-selective low-energy resonance on the orbital and a pseudogaplike spectral suppression on the orbital. High-throughput calculations across 27 compositions further show that X-Z sublattice tunes the Co--orbital interplay, producing strong, moderate, and weak interplay regimes. The moderate-interplay regime provides the key window for compensated ferrimagnetism and potential orbital-differentiated correlated state. These results identify off-stoichiometry Heusler-like compounds as a tunable platform for realizing correlated electronic states coupled to macroscopic magnetic compensation.