The manganese pnictide CaMn2Bi2, with Mn atoms arranged in a puckered honeycomb structure, exhibits narrow-gap antiferromagnetism, and it is currently a promising candidate for the study of complex electronic and magnetic phenomena, such as magnetotransport effects and potential spin spirals under high pressure. In this paper, we perform a detailed research of the magnetic properties of CaMn2Bi2 using density functional theory (DFT) combined with the Hubbard U correction and spin-orbit coupling, which accurately describe the magnetic interactions. Our results obtained for a large number of magnetic configurations are accurately captured by a modified Heisenberg model that includes on-site magnetization terms to describe magnetic energy excitations. We further investigate the role of the spin-orbit coupling, and find that the magnetic anisotropy of CaMn2Bi2 shows an easy plane, with the preferred magnetization direction being exchanged between axes in the plane by applying small strain values. This strain-tunable magnetization, driven by the interplay between spin-orbit interactions and lattice distortions, highlights the potential for controlling magnetic states in Mn-pnictides for future applications in spintronic and magnetoelectric devices.
@article{arxiv.2410.23053,
title = {Magnetic Order and Strain in Hexagonal Manganese Pnictide CaMn$_2$Bi$_2$},
author = {Rodrigo Humberto Aguilera-del-Toro and Mikel Arruabarrena and Aritz Leonardo and Martin Rodriguez-Vega and Gregory A. Fiete and Andrés Ayuela},
journal= {arXiv preprint arXiv:2410.23053},
year = {2026}
}