论文标题
费米表面形状对磁转运的影响：MNAS情况
Influence of the Fermi surface shape on magnetotransport: the MnAs case
论文作者
论文摘要
我们分析了费米表面（FS）形状对磁转运特性的影响，尤其是在MNAs化合物中的HALL效应上。在MNAS膜中观察到了相反的传导极性的证据，这些晶体方向（Goniopolarity）和具有施加磁场的载体类型的强依赖性。为了理解这种行为，我们开发了一个基于半经典方程的模型以及玻尔兹曼传输理论，该理论同时考虑了应用磁场和FS形状。 MNA化合物的FS是通过密度功能理论（DFT）获得的，显示了双曲体形状的明显优势。我们的研究证实，FS的这种特定拓扑会导致大厅运输中的刺激性行为。该理论结果得到了MNAS薄层对GAAS（001）和GAAS（111）（111）的MNA薄层上的磁转运测量的支持，在此过程中，这两种配置都使我们能够探索MNAS两个不同晶体方向的传输特性。
We analyze the influence of the Fermi surface (FS) shape on magnetotransport properties, particularly on the Hall effect in the MnAs compound. It has been observed in MnAs films evidence of opposite conduction polarities for different crystal direction (goniopolarity) and a strong dependence of the carrier type with applied magnetic field. In order to understand this behaviour, we developed a model based on the semiclassical equations along with Boltzmann transport theory that takes into account both, the applied magnetic field and the FS shape. The FS of the MnAs compound is obtained by means of density functional theory (DFT), showing a clear dominance of the hyperboloid shape. Our study, corroborate that this specific topology of the FS gives rise to a goniopolar behaviour in the Hall transport. This theoretical results are supported by magnetotransport measurements on MnAs thin layers epitaxially grown on GaAs(001) and GaAs(111), where both configurations allow us to explore the transport characteristics for two different crystal directions of the MnAs.
