论文标题
石墨烯对六角硼硝酸盐底物的异常光学响应
Anomalous optical response of graphene on hexagonal boron nitride substrates
论文作者
论文摘要
石墨烯/HBN异质结构可以被视为下一代光电子的基本构建块之一，主要是由于创纪录的电子迁移率。但是，目前，尽管对石墨烯/HBN异质结构的兴趣越来越兴趣，但目前，石墨烯内在的光学特性的研究仅限于标准底物（SIO2/SI，玻璃，石英）。这可以归因于确定HBN在总光学响应中强烈各向异性介电张量的具有挑战性的任务。在这项研究中，我们利用有或没有石墨烯单层的HBN的光学响应的同时分析来克服该问题。我们的技术使我们能够从250-950 nm的广泛光谱范围内从石墨烯/HBN异质结构中检索石墨烯的光学常数。我们的结果表明，石墨烯对HBN的吸收可能会超过Sio2/Si上的石墨烯，约60％。
Graphene/hBN heterostructures can be considered as one of the basic building blocks for the next-generation optoelectronics mostly owing to the record-high electron mobilities. However, currently, the studies of the intrinsic optical properties of graphene are limited to the standard substrates (SiO2/Si, glass, quartz) despite the growing interest in graphene/hBN heterostructures. This can be attributed to a challenging task of the determination of hBN's strongly anisotropic dielectric tensor in the total optical response. In this study, we overcome this issue through imaging spectroscopic ellipsometry utilizing simultaneous analysis of hBN's optical response with and without graphene monolayers. Our technique allowed us to retrieve the optical constants of graphene from graphene/hBN heterostructures in a broad spectral range of 250-950 nm. Our results suggest that graphene's absorption on hBN may exceed the one of graphene on SiO2/Si by about 60 %.
