A novel diluted magnetic semiconductor (Ca,Na)(Zn,Mn)2Sb2 with decoupled charge and spin dopings*

Abstract

We report the successful synthesis of a new diluted magnetic semiconductor (Ca,Na)(Zn,Mn)2Sb2. Na and Mn are doped into the parent compound CaZn2Sb2, which has the same crystal structure as that of “122” type iron-based superconductor CaFe2As2. Na substitution for Ca and Mn substitution for Zn introduce carriers and spins, respectively. Doping Mn atoms alone up to 5% does not induce any type of magnetic ordering. When both Na and Mn are co-doped, a ferromagnetic ordering with maximum T C ∼ 10 K has been observed. Iso-thermal magnetization shows that the coercive field is up to ∼ 245 Oe at 2 K. Below T C, a negative magneto-resistance with MR ∼ 12% has also been achieved.