Relationship among Structure, Disorder, Magnetism, and Band Topology in the MnSb₂Te₄·(Sb₂Te₃)n Family

The interplay between topology and magnetism induces various exotic quantum phenomena, with magnetic topological insulators (MTIs) serving as a prominent example due to their ability to host the quantum anomalous Hall effect (QAHE). However, the realization of the QAHE at a higher temperature approaching the magnetic transition temperature remains a significant challenge, primarily due to the scarcity of suitable material platforms and our limited understanding of the intricate relationships among band topology, magnetism, and defects. Here, we report a comprehensive investigation of MnSb2Te4·(Sb2Te3)n (n = 0–5) single crystals, including the discovery of the novel MnSb8Te13 pure phase. Experimental measurements confirm that MnSb8Te13 exhibits ferromagnetism and features topologically nontrivial electronic structures, characterized by a Dirac point located farther from the conduction band and a possible larger bulk gap compared to that of MnBi2Te4·(Bi2Te3)n (n = 0–3). Moreover, we systematically analyze the relationship among structure, magnetism, topology, and disorder within the Mn(Sb, Bi)2Te4·((Sb, Bi)2Te3)n family. This work will shed light on the exploration of potential platforms capable of achieving QAHE near the magnetic transition temperature, offering new directions for advancing topological quantum materials.