Tuning the Magnetic and Electrical Properties of Mn₃TeO₆ through Mg²⁺ Substitution

A major challenge in multiferroic materials research is the rigorous realisation of strong coupling at similar energy scales between two or more ferroic orders, e.g. ferroelectric and ferromagnetic ordering. One way to address this challenge is to atomically tune magnetic exchange interactions and electric dipoles through chemical substitution to potentially achieve enhanced magnetoelectric coupling. Mn3TeO6 is a multiferroic compound displaying spin spiral anti-ferromagnetic ordering (AFM). Substituting non-magnetic Mg²⁺ at the Mn²⁺ site could provide effective ways to modify the magnetic exchange interaction and lattice distortion, thereby tuning the magnetic and electric order parameters. Here we present the magnetic and electrical properties of Mn_3-xMg_xTeO₆ (0.75 < x < 3) systems. Magnetic susceptibility measurements show AFM ordering for the Mn-rich samples and magnetic frustrations for the S = 5/2 system. In addition, the heat capacity exhibits an anomaly at ~50–56 K, potentially related to structural/ferroelectric ordering. The results provide new insights into the ability to modify magnetic and electric order parameters at the atomic level.