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arXiv · 1409.2743

Sr$_{0.9}$K$_{0.1}$Zn$_{1.8}$Mn$_{0.2}$As$_{2}$: a ferromagnetic semiconductor with colossal magnetoresistance

Xiaojun Yang·Qian Chen·Yupeng Li·Zhen Wang·Jinke Bao·Yuke Li·Qian Tao·Guanghan Cao·Zhu-An Xu
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Abstract

A bulk diluted magnetic semiconductor (Sr,K)(Zn,Mn)$_{2}$As$_{2}$ was synthesized with decoupled charge and spin doping. It has a hexagonal CaAl$_{2}$Si$_{2}$-type structure with the (Zn,Mn)$_{2}$As$_{2}$ layer forming a honeycomb-like network. Magnetization measurements show that the sample undergoes a ferromagnetic transition with a Curie temperature of 12 K and \revision{magnetic moment reaches about 1.5 $μ_{B}$/Mn under $μ_0H$ = 5 T and $T$ = 2 K}. Surprisingly, a colossal negative magnetoresistance, defined as $[ρ(H)-ρ(0)]/ρ(0)$, up to $-$38\% under a low field of $μ_0H$ = 0.1 T and to $-$99.8\% under $μ_0H$ = 5 T, was observed at $T$ = 2 K. The colossal magnetoresistance can be explained based on the Anderson localization theory.

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Xiaojun Yang, Qian Chen, Yupeng Li, Zhen Wang, Jinke Bao, Yuke Li, Qian Tao, Guanghan Cao, Zhu-An Xu. 2014-09-09. Sr$_{0.9}$K$_{0.1}$Zn$_{1.8}$Mn$_{0.2}$As$_{2}$: a ferromagnetic semiconductor with colossal magnetoresistance. https://doi.org/10.1209/0295-5075%2F107%2F67007

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