Electrical Engineering Department, University of California at Los Angeles, CA 90095, USA.
Nanotechnology. 2010 Jun 25;21(25):255602. doi: 10.1088/0957-4484/21/25/255602. Epub 2010 May 28.
We report a 'superlattice' growth method to produce well-aligned magnetic MnGe nanocolumns and nanowells by using low-temperature molecular-beam epitaxy. Both structural and magnetic properties show strong evidence of Mn(5)Ge(3) precipitates and lattice-coherent nanostructures with different blocking temperatures. Magnetotransport measurements reveal positive and negative magnetoresistances for the nanowells and nanocolumns, respectively. This distinction can be explained by different spin scattering mechanisms under magnetic fields. Our results suggest a new growth strategy to achieve reproducible MnGe nanostructures, which facilitates the development of Ge-based spintronics and magnetoelectronics devices.
我们报告了一种“超晶格”生长方法，通过使用低温分子束外延来产生取向良好的磁性 MnGe 纳米柱和纳米井。结构和磁性性质都强烈表明存在 Mn(5)Ge(3)沉淀物和具有不同阻挡温度的晶格相干纳米结构。磁输运测量分别为纳米井和纳米柱呈现出正磁电阻和负磁电阻。这种区别可以通过磁场下不同的自旋散射机制来解释。我们的结果表明了一种实现可重复的 MnGe 纳米结构的新生长策略，这有助于基于 Ge 的自旋电子学和磁电子学器件的发展。
