Work

Hund’s physics-driven strong correlation in the altermagnet CaCrO3

Year: 2026

Type: article

Abstract: Altermagnetism has attracted intense interest, but strong correlation effects in altermagnets remain largely unexplored. Here, using density functional theory plus dynamical mean-field theory (DFT + DMFT), we identify CaCrO 3 , a rare example of a correlated metallic altermagnet with substantial Hund’s coupling. We show that Hundness leads to incoherent metallicity with altermagnetic spin splitting and sustains local spin moments. The DFT + DMFT-calculated magnetic moment (~ 1.3 µ B /Cr) is in quantitative agreement with neutron diffraction (~ 1.2 µ B /Cr), while conventional DFT + U predicts an insulating state instead. Furthermore, Hundness promotes incipient flat bands and gives rise to heavy-fermion-like behavior in this 3 d system, with effective mass enhancement m * / m ~ 47. This work demonstrates DFT + DMFT as a reliable computational tool for studying strongly correlated altermagnets and highlights the importance of Hund’s physics in these emerging materials.

Source: npj Computational Materials

DOI: 10.1038/s41524-026-02392-4

Authors: Zhenfeng Ouyang, Peng-Jie Guo, Rong-Qiang He, Zhong-Yi Lu

Institutions: Ningbo University, Renmin University of China

Language: English

Topic: Advanced Condensed Matter Physics

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,490

Funders: National Natural Science Foundation of China, Renmin University of China