Resistance of single domain walls in half-metallic CrO 2 epitaxial nanostructures
Resistance of single domain walls in half-metallic CrO 2 epitaxial nanostructures
复制标题
半金属CrO 2 外延纳米结构中单畴壁的电阻
DOI：
10.1039/d1nr05555k
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发表时间：
2021
期刊：
影响因子：
6.7
通讯作者：
Xiao, Gang
中科院分区：
文献类型：
--
作者：
Qian, Lijuan;Zhou, Shiyu;Wang, Kang;Xiao, Gang
磁畴结构是一种活跃的电子传输剂，可以用来诱导大磁阻，特别是在半金属固体中。我们研究了沟道宽度(D)为30~200 nm的一维半金属CrO2纳米导体中单个磁畴壁引起的超额电阻。我们观察到，当d从200 nm减小到30 nm时，域壁诱导的MR增加了70倍。我们推测，这种增强是由于磁区壁阻(DWR)的增加和弹道磁阻(BMR)的额外贡献。我们发现d对磁畴壁诱导的MR有较大的尺寸效应，其大小随d As d−的增大而增大。因此，我们预测一根简单的CrO2纳米线在150 nm~2的横截面上浸渍有一个紧缩层，其磁共振率可以达到100%。这种巨大的磁流变远远超过了传统的铁磁纳米线，证实了半金属性在增强磁传输中的作用。
Magnetic domain structures are active electron transport agents and can be used to induce large magnetoresistance (MR), particularly in half-metallic solids. We have studied the excess resistance induced by a single magnetic domain wall in a one-dimensional half-metallic CrO2 nanoscale conductor with a built-in constriction whose channel width (d) ranges from 30 to 200 nm. We observed that the domain wall-induced MR is enhanced by 70 fold when d decreases from 200 nm to 30 nm. We speculate that the enhancement is due to the increased domain wall resistance (DWR) and the extra contribution of ballistic magnetoresistance (BMR). We have uncovered a large size effect of d on the MR induced by the domain wall, which scales with d as d−1.87±0.32. Accordingly, we predict that the MR ratio of a simple CrO2 nanowire impregnated with a constriction at a 150 nm2 cross-section could reach 100%. This large MR far exceeds that of a conventional ferromagnetic nanowire, confirming the role of half metallicity on enhanced magneto-transport.