Positive colossal magnetoresistance observed in Co doped amorphous carbon/silicon heterostructures
Positive colossal magnetoresistance observed in Co doped amorphous carbon/silicon heterostructures
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DOI：
10.1063/1.4765648
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发表时间：
2012-11
影响因子：
4
通讯作者：
Y. C. Jiang;J. Gao
中科院分区：
文献类型：
--
作者：
Y. C. Jiang;J. Gao
采用脉冲激光沉积法在n型Si衬底上制备了Co掺杂非晶碳（Co-C）/Si异质结构。在55-240 K的温度范围内，异质结表现出正的庞磁电阻效应。反向偏置电压的磁阻（MR）在5 T时达到约270%，而正向偏置下的MR仅为7%。此外，透射电镜结果表明，Co原子在Co-C/Si界面处有聚集的趋势。Co在界面上的聚集可能是正CMR效应的一个可能来源。
Heterostructures of Co-doped amorphous carbon (Co-C)/silicon were fabricated by growing Co-C films on n-type Si substrates using pulsed laser deposition. The heterostructures exhibited a positive colossal magnetoresistance (CMR) effect over a temperature range of 55-240 K. The magnetoresistance (MR) for the reverse bias voltage reached around 270% at 5 T, whereas the MR under a forward bias was 7% only. Besides, the transmission electron microscopy results demonstrate that Co atoms tended to be aggregated at Co-C/Si interface. The Co aggregation in the interface may be a possible origin of the positive CMR effect.