Plasmon transport and its guiding in graphene
Plasmon transport and its guiding in graphene
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DOI：
10.1088/1367-2630/16/6/063055
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发表时间：
2014-06
影响因子：
3.3
通讯作者：
N. Kumada;R. Dubourget;K. Sasaki;Shin-ichi Tanabe;Hiroki Hibino;Hiroshi Kamata;M. Hashisaka;K. Muraki;T. Fujisawa
中科院分区：
文献类型：
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作者：
N. Kumada;R. Dubourget;K. Sasaki;Shin-ichi Tanabe;Hiroki Hibino;Hiroshi Kamata;M. Hashisaka;K. Muraki;T. Fujisawa
用时间分辨电学测量方法研究了等离子体在石墨烯中的输运。我们证明了等离子体激元模式的速度v(或折射率∝v−1)和特性阻抗Z可以通过载流子浓度来调节。通过利用Z可调谐特性，我们提出了一种门限等离子体波导。栅定义波导的一个重要优点是导通特性随栅电压的动态切换。人们可以定制门电极的图案来定义从源波导分出的两个输出波导，并且可以通过改变门电压来切换输出波导。实际上，我们展示了在Y形通道中的路径选择：可以通过调整每条路径的Z来选择用于等离子体传输的路径。这些结果可以通过模拟很好地再现，从而鼓励基于石墨烯的等离子体器件的设计。
Transport of plasmons in graphene has been investigated by time-resolved electrical measurements. We demonstrate that the velocity v (or the refractive index ∝ v − 1 ?> ) and the characteristic impedance Z of the plasmon mode can be tuned through the carrier density. By exploiting the Z tunability, we present a gate-defined plasmonic waveguide. An important advantage of the gate-defined waveguide is dynamical switching of guiding characteristics with the gate voltages. One can tailor the patterns of gate electrodes to define two output waveguides branching off from a source waveguide, and the output waveguide can be switched by changing the gate voltages. Indeed, we show the routing in a Y-shaped channel: the path for the plasmon transmission can be selected by tuning Z of each path. These results can be well reproduced by simulation, encouraging the design of graphene-based plasmonic devices.