Magnetic and electronic properties of KMn1-xMxBi (M = Cu, Mg, Zn) solid solutions

Abstract

Materials displaying antiferromagnetic exchange interactions are promising for spintronic applications. The ability to control exchange interactions and electronic properties of antiferromagnetic materials is key in this context. Here, we investigate by means of first-principles calculations to what extent the structural, electronic and magnetic properties of the KMnBi compound can be tailored through chemical doping. It is shown that the KMnBi compound features antiferromagnetic ordering and a direct gap of 0.287 eV. It is found that all solid solutions of KMn0.5M0.5Bi (M = Cu, Mg, Zn) present antiferromagnetic behavior in the ground state. In contrast, the compositions of KMn0.75M0.25Bi (M = Cu, Mg, Zn) are ferrimagnetic with total magnetization of 3.89 /cell, 4.45 /cell, and 4.41 /cell for 25%Cu, 25%Mg and 25%Zn doped KMnBi, respectively. This study shows that the magnetic response of KMnBi can be manipulated to its advantage by appropriately substituting transition metals in the Mn cell site. As a result, transition metal doped KMnBi could have potential applications based on their magnetic response, in particular, in magnetic spintronics.