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arXiv · 2408.08835

Altermagnetism in the layered intercalated transition metal dichalcogenide CoNb$_4$Se$_8$

Resham Babu Regmi·Hari Bhandari·Bishal Thapa·Yiqing Hao·Nileema Sharma·James McKenzie·Xinglong Chen·Abhijeet Nayak·Mohamed El Gazzah·Bence Gábor Márkus·László Forró·Xiaolong Liu·Huibo Cao·J. F. Mitchell·I. I. Mazin·Nirmal J. Ghimire
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Abstract

Altermagnets (AMs) are a new class of magnetic materials that combine the beneficial spintronics properties of ferromagnets and antiferromagnets, garnering significant attention recently. Here, we have identified altermagnetism in a layered intercalated transition metal diselenide, CoNb$_4$Se$_8$, which crystallizes with an ordered sublattice of intercalated Co atoms between NbSe$_2$ layers. Single crystals are synthesized, and the structural characterizations are performed using single crystal diffraction and scanning tunneling microscopy. Magnetic measurements reveal easy-axis antiferromagnetism below 168 K. Density functional theory (DFT) calculations indicate that A-type antiferromagnetic ordering with easy-axis spin direction is the ground state, which is verified through single crystal neutron diffraction experiments. Electronic band structure calculations in this magnetic state display spin-split bands, confirming altermagnetism in this compound. The layered structure of CoNb$_4$Se$_8$ presents a promising platform for testing various predicted properties associated with altermagnetism.

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Resham Babu Regmi, Hari Bhandari, Bishal Thapa, Yiqing Hao, Nileema Sharma, James McKenzie, Xinglong Chen, Abhijeet Nayak, Mohamed El Gazzah, Bence Gábor Márkus, László Forró, Xiaolong Liu, Huibo Cao, J. F. Mitchell, I. I. Mazin, Nirmal J. Ghimire. 2024-08-16. Altermagnetism in the layered intercalated transition metal dichalcogenide CoNb$_4$Se$_8$. https://doi.org/10.1038/s41467-025-58642-4

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