Zeng Hong-Li, Guo Yan-Dong, Yan Xiao-Hong, Zhou Jie
College of Natural Science, Nanjing University of Posts and Telecommunications, Nanjing 210046, China.
Phys Chem Chem Phys. 2017 Aug 16;19(32):21507-21513. doi: 10.1039/c7cp02862h.
Spin caloritronics has drawn much attention as it combines thermoelectrics and spintronics together. Carbon-based structures, such as graphene, have been found to exhibit different kinds of spin caloritronic features. However, a study of spin caloritronics in carbon nanotubes (CNTs) is still lacking. Using first-principles calculations, we investigate the spin-Seebeck effect (SSE) in partially hydrogenated CNTs. It is found that linear hydrogenation could make CNTs acquire magnetism and exhibit the spin-Seebeck effect. Moreover, an odd-even effect of the SSE is observed, where the even cases could be used as spin-Seebeck diodes. Further analysis shows that, it is induced by the difference of band structures, where the band structure of a tube is a combination of that of graphene-nanoribbon parts "divided" by hydrogenation. This mechanism could be extended to nanotubes with different diameters, showing great application potential. We believe that our results are very useful for the development of nanotube-based spin caloritronic devices.
自旋热电子学因其将热电学和自旋电子学结合在一起而备受关注。人们发现，诸如石墨烯之类的碳基结构展现出了不同类型的自旋热电子学特性。然而，对碳纳米管（CNT）中的自旋热电子学研究仍然不足。我们采用第一性原理计算方法，研究了部分氢化碳纳米管中的自旋塞贝克效应（SSE）。研究发现，线性氢化可使碳纳米管获得磁性并展现出自旋塞贝克效应。此外，还观察到了自旋塞贝克效应的奇偶效应，其中偶数情况可用作自旋塞贝克二极管。进一步分析表明，这是由能带结构差异引起的，其中碳纳米管的能带结构是由氢化“分割”而成的石墨烯纳米带部分的能带结构组合。这种机制可扩展到不同直径的纳米管，显示出巨大的应用潜力。我们相信，我们的结果对于基于纳米管的自旋热电子学器件的发展非常有用。
