Hajlaoui Mahdi, Sediri Haikel, Pierucci Debora, Henck Hugo, Phuphachong Thanyanan, Silly Mathieu G, de Vaulchier Louis-Anne, Sirotti Fausto, Guldner Yves, Belkhou Rachid, Ouerghi Abdelkarim
CNRS- Laboratoire de Photonique et de Nanostructures, Route de Nozay, 91460 Marcoussis, France.
Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France.
Sci Rep. 2016 Jan 7;6:18791. doi: 10.1038/srep18791.
The van de Waals heterostructure formed by an epitaxial trilayer graphene is of particular interest due to its unique tunable electronic band structure and stacking sequence. However, to date, there has been a lack in the fundamental understanding of the electronic properties of epitaxial trilayer graphene. Here, we investigate the electronic properties of large-area epitaxial trilayer graphene on a 4° off-axis SiC(0001) substrate. Micro-Raman mappings and atomic force microscopy (AFM) confirmed predominantly trilayer on the sample obtained under optimized conditions. We used angle-resolved photoemission spectroscopy (ARPES) and Density Functional Theory (DFT) calculations to study in detail the structure of valence electronic states, in particular the dispersion of π bands in reciprocal space and the exact determination of the number of graphene layers. Using far-infrared magneto-transmission (FIR-MT), we demonstrate, that the electron cyclotron resonance (CR) occurs between Landau levels with a (B)(1/2) dependence. The CR line-width is consistent with a high Dirac fermions mobility of ~3000 cm(2)·V(-1)·s(-1) at 4 K.
由外延三层石墨烯形成的范德华异质结构因其独特的可调节电子能带结构和堆叠顺序而备受关注。然而，迄今为止，对外延三层石墨烯的电子特性仍缺乏基本的了解。在此，我们研究了在4°离轴SiC(0001)衬底上大面积外延三层石墨烯的电子特性。显微拉曼映射和原子力显微镜（AFM）证实，在优化条件下获得的样品主要为三层结构。我们使用角分辨光电子能谱（ARPES）和密度泛函理论（DFT）计算来详细研究价电子态的结构，特别是倒易空间中π带的色散以及石墨烯层数的精确确定。利用远红外磁透射（FIR-MT），我们证明电子回旋共振（CR）发生在朗道能级之间，具有B(1/2)依赖性。在4K时，CR线宽与约3000 cm2·V-1·s-1的高狄拉克费米子迁移率一致。
