Plasmonics of coupled graphene micro-structures
Plasmonics of coupled graphene micro-structures
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DOI：
10.1088/1367-2630/14/12/125001
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发表时间：
2012-05
影响因子：
3.3
通讯作者：
Hugen Yan;F. Xia;Zhiqiang Li;P. Avouris
中科院分区：
文献类型：
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作者：
Hugen Yan;F. Xia;Zhiqiang Li;P. Avouris
在远红外光谱范围内，石墨烯微结构(如微带和圆盘)的光学响应主要受局域等离子体共振的影响。通常涉及到这种结构的集合，各个结构之间的耦合效应预计将发挥重要作用。本文研究了不同构型石墨烯微结构的等离子体相互作用。在同一平面上，石墨烯圆盘之间的耦合相对较弱，而垂直堆积的石墨烯圆盘之间的耦合较强，共振频率急剧增加。在更复杂的结构中的等离子体可以被看作是来自更基本结构的等离子体的杂交。作为例子，给出了石墨烯微环的等离子体共振，以及它们在磁场中的响应。最后，通过在500 cm−1附近观察到一个新的混合共振峰，证实了等离子体激元与SiO_2衬底表面极性声子的耦合。
The optical response of graphene micro-structures, such as micro-ribbons and discs, is dominated by the localized plasmon resonance in the far infrared spectral range. An ensemble of such structures is usually involved and the effect of the coupling between the individual structures is expected to play an important role. In this paper, plasmonic coupling of graphene micro-structures in different configurations is investigated. Whereas a relatively weak coupling between graphene discs on the same plane is observed, the coupling between vertically stacked graphene discs is strong and a drastic increase of the resonance frequency is demonstrated. The plasmons in a more complex structure can be treated as the hybridization of plasmons from more elementary structures. As an example, the plasmon resonances of graphene micro-rings are presented, in conjunction with their response in a magnetic field. Finally, the coupling of the plasmon and the surface polar phonons of SiO2 substrate is demonstrated by the observation of a new hybrid resonance peak around 500 cm−1.