Physical Properties of Fe-doped Ba(Mn$_{\mathrm{1-x}}$Fe$_{\mathrm{x}})_{\mathrm{2}}$Sb$_{\mathrm{2}}$ Single Crystals

BaMn$_{\mathrm{2}}$Sb$_{\mathrm{2}}$ forms the ThCr$_{\mathrm{2}}$Si$_{\mathrm{2}}$-type crystal structure and has the magnetic semiconducting ground state. In attempt to alter its ground-state properties, Mn is partially substituted by Fe resulting in Ba(Mn$_{\mathrm{1-x}}$Fe$_{\mathrm{x}})_{\mathrm{2}}$Sb$_{\mathrm{2}}$. While the doped system remains the same structure for x $\le $ 0.5, its electrical and thermal conductivity decreases with increasing x, suggesting that doping-induced disorder plays an important role. Magnetically, we find that, with increasing x, the magnetic transition temperature T$_{\mathrm{M}}$ decreases (from 700 K for x $=$ 0 to 500 K for x $=$ 0.5) but magnetic susceptibility increases above and below T$_{\mathrm{M}}$. These and low-temperature magnetization anisotropy suggest the canted-antiferromagnetic configuration with net magnetic moment in BaMn$_{\mathrm{2}}$Sb$_{\mathrm{2}}$. The antiferromagnetic interaction is gradually suppressed upon Fe doping, leading to the enhanced ferromagnetic component in Ba(Mn$_{\mathrm{1-x}}$Fe$_{\mathrm{x}})_{\mathrm{2}}$Sb$_{\mathrm{2}}$.