Mn substitution induced a ferrimagnetic to ferromagnetic transition in trigonal ${\text{Cr}}_5{\text{Te}}_8$

Abstract

Tailoring the magnetic properties of chromium tellurides via heterointercalation with extrinsic transition metals remains largely unexplored. Here, we report a comprehensive investigation of trigonal Cr${}_5$Te${}_8$ and Cr${}_4$MnTe${}_8$ single crystals, in which Mn substitution elevates the magnetic ordering temperature from 226 to 249 K and enhances the saturation magnetic moment per magnetic ion ($m_{\text{S}}$) from 2.00 to 2.66 ${\mu }_{\text{B}}$ at 5 K. Remarkably, the observed $m_{\text{S}}$ enhancement significantly exceeds the contribution of Mn ion moments alone, indicating the relief of intrinsic spin compensation within the parent lattice. First-principles calculations definitively establish that pristine ${\text{Cr}}_5{\text{Te}}_8$ exhibits ferrimagnetic ordering with a computed $m_{\text{S}}$ of 1.98~${\mu }_{\text{B}}$, and further reveal that preferential occupation of the van der Waals gaps by Mn ions induces a ferrimagnetic-to-ferromagnetic transition, yielding a predicted $m_{\text{S}}$ of 2.94~${\mu }_{\text{B}}$. These findings not only resolve the magnetic ground state of trigonal Cr${}_5$Te${}_8$ but also identify heterointercalation as a robust strategy for engineering the spin textures of chromium tellurides.