Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Center for Nanochemistry, Beijing 100871, People's Republic of China.
Nano Lett. 2010 Aug 11;10(8):2870-6. doi: 10.1021/nl100938e.
The authors present a van der Waals epitaxy of high-quality ultrathin nanoplates of topological insulator Bi(2)Se(3) on a pristine graphene substrate using a simple vapor-phase deposition method. Sub-10-nm-thick nanoplates of layered Bi(2)Se(3) with defined orientations can be epitaxially grown on a few-layer pristine graphene substrate. We show the evolution of Raman spectra with the number of Bi(2)Se(3) layers on few-layer graphene. Bi(2)Se(3) nanoplates with a thickness of three quintuple-layers (3-QL) exhibit the strongest Raman intensity. Strain effects in the Bi(2)Se(3)/graphene nanoplate heterostructures is also studied by Raman spectroscopy. 1-QL and 2-QL Bi(2)Se(3) nanoplates experience tensile stress, consistent with compressive stress in single-layer and bilayer graphene substrates. Our results suggest an approach for the synthesis of epitaxial heterostructures that consist of an ultrathin topological insulator and graphene, which may be a new direction for electronic and spintronic applications.
作者使用简单的气相沉积方法，在原始石墨烯衬底上展示了高质量的拓扑绝缘体 Bi(2)Se(3)超薄纳米板的范德华外延。亚 10nm 厚的具有确定取向的层状 Bi(2)Se(3)纳米板可以在几层原始石墨烯衬底上外延生长。我们展示了拉曼光谱随几层石墨烯上 Bi(2)Se(3)层数的演变。厚度为三个五倍层(3-QL)的 Bi(2)Se(3)纳米板表现出最强的拉曼强度。通过拉曼光谱还研究了 Bi(2)Se(3)/石墨烯纳米板异质结构中的应变效应。1-QL 和 2-QL Bi(2)Se(3)纳米板经历张应变，与单层和双层石墨烯衬底中的压应变一致。我们的结果表明了一种合成由超薄拓扑绝缘体和石墨烯组成的外延异质结构的方法，这可能是电子和自旋电子应用的一个新方向。
