Cu2(Zn,Mn)(Sn,Al)Se4: A diluted magnetic semiconductor with decoupled charge and spin doping.

• Cu 2 (Zn,Mn)(Sn,Al)Se 4 are new bulk form DMSs with decoupled charge and spin doping. • Only when Mn and Al are doped simultaneously can ferromagnetic ordering form. • Over or less of carriers for fix Mn concentration are both harmful to ferromagnetism. • Cu 2 (Zn,Mn)(Sn,Al)Se 4 have a negative magneto-resistance effect. We report the successful synthesis and characterization of a diluted magnetic semiconductor Cu 2 (Zn,Mn)(Sn,Al)Se 4 with stannite structure. 15% of Mn doping into the quaternary semiconductor Cu 2 ZnSnSe 4 does not induce any type of magnetic ordering. Only when Al is codoped with Mn, is ferromagnetic transition observed in Cu 2 (Zn,Mn)(Sn,Al)Se 4. Our results demonstrate that Mn substitution for Zn introduces local moments, while Al substitution for Sn introduces carriers, respectively. Both spins and carriers are crucial in the formation of ferromagnetic ordering in Cu 2 (Zn,Mn)(Sn,Al)Se 4. [ABSTRACT FROM AUTHOR]