By first-principles calculations, we study the magnetic and topological properties of $\mathit{XY}{\mathrm{Bi}}_2{\mathrm{Te}}_5$-family $(X, Y=\mathrm{Mn},\mathrm{Ni},\mathrm{V},\mathrm{Eu})$ compounds. The strongly coupled double magnetic atom-layers can significantly enhance the magnetic ordering temperature while keeping the topologically nontrivial properties. Particularly, ${\mathrm{NiVBi}}_2{\mathrm{Te}}_5$ is found to be a magnetic Weyl semimetal in bulk and a Chern insulator in thin film with both the Curie temperature ($\sim 150$ K) and full gap well above 77 K. ${\mathrm{Ni}}_2{\mathrm{Bi}}_2{\mathrm{Te}}_5, {\mathrm{MnNiBi}}_2{\mathrm{Te}}_5, {\mathrm{NiVBi}}_2{\mathrm{Te}}_5$, and ${\mathrm{NiEuBi}}_2{\mathrm{Te}}_5$ exhibit intrinsic dynamic axion state. Among them, ${\mathrm{MnNiBi}}_2{\mathrm{Te}}_5$ has a Néel temperature over 200 K and ${\mathrm{Ni}}_2{\mathrm{Bi}}_2{\mathrm{Te}}_5$ even demonstrates antiferromagnetic order above room temperature. These results indicate an approach to realize high-temperature quantum anomalous Hall effect and other topological quantum effects for practical applications.

• Received 9 December 2022
• Revised 5 July 2023
• Accepted 24 July 2023

DOI:https://doi.org/10.1103/PhysRevB.108.075117