Colossal negative magnetoresistance in spin glass Na(Zn,Mn)Sb

Abstract We report the study of magnetic and transport properties of polycrystalline and single crystal Na(Zn,Mn)Sb, a new member of “111” type of diluted magnetic materials. The material crystallizes into Cu 2 Sb-type structure which is isostructural to “111” type Fe-based superconductors. With suitable carrier and spin doping, the Na(Zn,Mn)Sb establishes spin-glass ordering with freezing temperature ( T f ) below 15 K. Despite lack of long-range ferromagnetic ordering, Na(Zn,Mn)Sb single crystal still shows sizeable anomalous Hall effect below T f . Carrier concentration determined by Hall effect measurements is over 10 19 cm –3 . More significantly, we observe colossal negative magnetoresistance (MR ≡ [ ρ ( H ) − ρ (0)]/ ρ (0)) of –94% in the single crystal sample.