Comment: "Electrical injection and detection of spin accumulation in silicon at 500 K with magnetic metal / silicon dioxide contacts" [Nature Commun. 2:245 doi:10.1038/ncomms125 (2011)]
Comment: "Electrical injection and detection of spin accumulation in silicon at 500 K with magnetic metal / silicon dioxide contacts" [Nature Commun. 2:245 doi:10.1038/ncomms125 (2011)]
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评论：“使用磁性金属/二氧化硅接触在 500 K 下对硅中自旋积累进行电注入和检测”[Nature Commun.
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
B. Jonker
中科院分区：
文献类型：
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作者：
C. H. Li;O. V. Erve;B. Jonker
在最近的一篇出版物中，我们展示了在三端几何结构中使用铁磁金属/SiO2 隧道势垒接触在高达 500K 的温度下在 n 型硅中进行电自旋注入和检测（Nature Commun. 2:245 doi:10.1038/ncomms125 (2011)）。在将我们测得的自旋电压信号与理论预测值进行比较时，我们遵循了 Tran 等人 (Phys. Rev. Lett. 102, 036601 (2009)) 的分析，并无意中传播了其中发现的错误。正如他们在最近的勘误表 (arXiv:0810.4770v2) 中指出的那样，自旋扩散长度 LSD 远小于接触宽度或沟道厚度（我们的实验情况）的样品理论中自旋阻力面积乘积的正确表达式由乘积 {gamma}^2 {rho} LSD 给出，其中 {gamma} 是隧道自旋极化，{rho} 是 半导体传输通道的电阻率。通过这种修正，我们测量的自旋电压比理论预测的大得多，而不是像我们所说的那样非常一致。我们强调，我们论文的基本结论是相同的——电子自旋寿命随着电子密度的增加而系统性降低，这表明自旋在硅通道中积累，而不是在界面态中积累。我们进一步表明，测量的自旋寿命基本上与隧道势垒材料（SiO2、Al2O3、MgO）或所使用的磁性金属（Fe、CoFe、NiFe）无关，表明测量的自旋寿命与 Si 的特性有明显的相关性，与隧道势垒/界面或磁性金属的相关性很小。
In a recent publication, we demonstrated electrical spin injection and detection in n-type silicon at temperatures up to 500K using ferromagnetic metal / SiO2 tunnel barrier contacts in a three-terminal geometry (Nature Commun. 2:245 doi:10.1038/ncomms125 (2011)). In comparing our measured spin-voltage signal with the value predicted by theory, we followed the analysis of Tran et al, (Phys. Rev. Lett. 102, 036601 (2009)), and inadvertently propagated an error found therein. As they note in a recent erratum (arXiv:0810.4770v2), the correct expression for the spin resistance area product from the theory for a sample with a spin diffusion length LSD much less than the contact width or channel thickness (our experimental situation) is given by the product {gamma}^2 {rho} LSD, where {gamma} is the tunneling spin polarization, and {rho} is the resistivity of the semiconductor transport channel. With this correction, our measured spin voltages are much larger than those predicted by theory, rather than in good agreement as we stated. We emphasize that the basic conclusions of our paper are the same - the systematic decrease in electron spin lifetime with increasing electron density demonstrates spin accumulation in the Si channel rather than in interface states. We further show that the measured spin lifetimes are essentially independent of the tunnel barrier material (SiO2, Al2O3, MgO) or the magnetic metal used (Fe, CoFe, NiFe), demonstrating clear correlation of the measured spin lifetime with the character of the Si, and little correlation with the tunnel barrier / interface or magnetic metal.