Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA.
Nano Lett. 2012 Apr 11;12(4):1972-6. doi: 10.1021/nl204510p. Epub 2012 Apr 2.
We report the synthesis of single crystalline Co(2)Si nanowires and the electrical transport studies of single Co(2)Si nanowire devices at low temperature. The butterfly shaped magnetoresistance shows interesting ferromagnetic features, including negative magnetoresistance, hysteretic switch fields, and stepwise drops in magnetoresistance. The nonsmooth stepwise magnetoresistance response is attributed to magnetic domain wall pinning and depinning motion in the Co(2)Si nanowires probably at crystal or morphology defects. The temperature dependence of the domain wall depinning field is observed and described by a model based on thermally assisted domain wall depinning over a single energy barrier.
我们报告了单晶 Co(2)Si 纳米线的合成以及低温下单 Co(2)Si 纳米线器件的输运研究。蝴蝶形磁阻表现出有趣的铁磁特征，包括负磁阻、滞后开关场和磁阻的阶跃下降。非平滑阶跃磁阻响应归因于 Co(2)Si 纳米线中的磁畴壁钉扎和去钉扎运动，可能是在晶体或形态缺陷处。观察到畴壁去钉扎场的温度依赖性，并通过基于单个能量势垒上热辅助畴壁去钉扎的模型进行描述。
