(Ca,Na)(Zn,Mn)2As2: A new spin and charge doping decoupled diluted ferromagnetic semiconductor

Here, we report the successful synthesis of a spin- and charge-decoupled diluted magnetic semiconductor (DMS) (Ca,Na)(Zn,Mn)2As2, crystallizing into the hexagonal CaAl2Si2 structure. The compound shows a ferromagnetic transition with a Curie temperature up to 33 K with 10% Na doping, which gives rise to carrier density of np ∼ 1020 cm−3. The new DMS is a soft magnetic material with HC < 400 Oe. The anomalous Hall effect is observed below the ferromagnetic ordering temperature. With increasing Mn doping, ferromagnetic order is accompanied by an interaction between the local spin and mobile charge, giving rise to a minimum in resistivity at low temperatures and localizing the conduction electrons. The system provides an ideal platform for studying the interaction of the local spins and conduction electrons.