arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1310.8044cond-mat.mes-hall
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石墨烯与六方氮化硼电子相互作用的光学探测

Optical Probing of Electronic Interaction between Graphene and Hexagonal Boron Nitride

Gwanghyun Ahn, Hye Ri Kim, Taeg Yeoung Ko, Kyoungjun Choi, Kenji Watanabe, Takashi Taniguchi, Byung Hee Hong, Sunmin Ryu

摘要:

由于二维固体的低维性,即使二维固体之间的弱范德华(vdW)粘附也可能干扰它们的各种材料性质。虽然石墨烯的电子结构已经被预测通过vdW与其他材料的相互作用而被修改,但其光学表征尚未成功。在这份报告中,我们证明,拉曼光谱可以用来检测几个百分点的减少费米速度(vF)的石墨烯所造成的vdW与底层的六方氮化硼(hBN)的相互作用。我们的研究还建立了拉曼光谱分析,使vdW相互作用的影响,从那些由机械应变或额外的载流子分离。分析表明,hBN上的石墨烯的光谱特征主要受vF和机械应变的变化的影响,但不像SiO2衬底上的石墨烯负载的电荷掺杂。还发现hBN上的石墨烯对热诱导空穴掺杂不太敏感。

英文摘要:

Even weak van der Waals (vdW) adhesion between two-dimensional solids may perturb their various materials properties owing to their low dimensionality. Although the electronic structure of graphene has been predicted to be modified by the vdW interaction with other materials, its optical characterization has not been successful. In this report, we demonstrate that Raman spectroscopy can be utilized to detect a few % decrease in the Fermi velocity (vF) of graphene caused by the vdW interaction with underlying hexagonal boron nitride (hBN). Our study also establishes Raman spectroscopic analysis which enables separation of the effects by the vdW interaction from those by mechanical strain or extra charge carriers. The analysis reveals that spectral features of graphene on hBN are mainly affected by change in vF and mechanical strain, but not by charge doping unlike graphene supported on SiO2 substrates. Graphene on hBN was also found to be less susceptible to thermally induced hole doping.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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