Hund's physics extends to actinide f electron systems
Byungkyun Kang, Roy N. Herrera-Navarro, Stephen S. Micklo, Mark R. Pederson, Eunja Kim
公開日: 2025/9/27
Abstract
Uranium 5f electrons often yield heavy-fermion behavior via Kondo screening. However, the pronounced bad-metallic transport of uranium mononitride (UN) defies an incoherent Kondo explanation. Using density-functional theory combined with dynamical mean-field theory, we show that UN is a strongly correlated bad metal. The dominant correlations arise from intra-atomic Hund's exchange interaction between two 5f electrons, which aligns local magnetic moments and produces large quasiparticle mass renormalization. This identifies UN as a 5f-electron analogue of a Hund's metal-a paradigm chiefly associated with transition-metal d systems. Our results motivate a re-examination of the interplay between Mott, Kondo, and Hund-driven correlations across actinide correlated materials.