The dense Kondo lattice Ce5CoGe2 exhibits superconductivity once the magnetic ordering is suppressed by pressure. Here the ambient pressure magnetic state is investigated via magnetization, heat capacity, powder neutron diffraction, and muon spin relaxation (μSR) measurements. Neutron diffraction results reveal a noncollinear ferromagnetic structure, where the four inequivalent Ce sites exhibit different magnetic moments. Point-charge model calculations of the crystalline-electric field (CEF) ground states corroborate different moments between the sites, and suggest sizeable components of the moments along different directions, consistent with the non-collinear structure. Analysis of the Dzyaloshinskii-Moriya (DM) interaction for the bonds connecting Ce atoms demonstrates that most of these bonds exhibit a nonzero DM vector, suggesting that competition between intersite magnetic exchange interactions, CEF driven single-ion anisotropy, the Kondo effect and the DM interaction may drive the non-collinear ferromagnetism.
@article{arxiv.2603.19592,
title = {Non-collinear ferromagnetism in the Kondo lattice Ce$_5$CoGe$_2$},
author = {Jinyu Wu and Jiawen Zhang and Toni Shiroka and Shams Sohel Islam and Mingyi Wang and Yongjun Zhang and Devashibhai T. Adroja and Yu Liu and Huiqiu Yuan and Michael Smidman},
journal= {arXiv preprint arXiv:2603.19592},
year = {2026}
}