García-Ruiz Aitor, Slizovskiy Sergey, Mucha-Kruczyński Marcin, Fal'ko Vladimir I
Department of Physics , University of Bath , Claverton Down , Bath BA2 3FL , United Kingdom.
National Graphene Institute , University of Manchester , Booth Street E , Manchester M13 9PL , United Kingdom.
Nano Lett. 2019 Sep 11;19(9):6152-6156. doi: 10.1021/acs.nanolett.9b02196. Epub 2019 Aug 7.
Rhombohedral graphite features peculiar electronic properties, including persistence of low-energy surface bands of a topological nature. Here, we study the contribution of electron-hole excitations toward inelastic light scattering in thin films of rhombohedral graphite. We show that, in contrast to the featureless electron-hole contribution toward Raman spectrum of graphitic films with Bernal stacking, the inelastic light scattering accompanied by electron-hole excitations in crystals with rhombohedral stacking produces distinct features in the Raman signal which can be used both to identify the stacking and to determine the number of layers in the film.
菱方石墨具有独特的电子特性,包括具有拓扑性质的低能表面能带的持续性。在此,我们研究了电子 - 空穴激发对菱方石墨薄膜中非弹性光散射的贡献。我们表明,与具有伯纳尔堆叠的石墨薄膜的拉曼光谱中无特征的电子 - 空穴贡献不同,在具有菱方堆叠的晶体中,伴随电子 - 空穴激发的非弹性光散射在拉曼信号中产生了独特的特征,这些特征可用于识别堆叠方式并确定薄膜中的层数。