Tunable graphene near-IR dielectric loaded waveguides
Tunable graphene near-IR dielectric loaded waveguides
复制标题
可调谐石墨烯近红外电介质负载波导
DOI：
10.1088/0022-3727/49/26/265102
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Shi Wangzhou
中科院分区：
文献类型：
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作者：
Liu Chunlin;He Xiaoyong;Zhao Zhenyu;Lin Fangting;Liu Feng;Shi Wangzhou
通过将石墨烯层与介质加载的表面等离子体激元波导集成，研究了工作频率、石墨烯层费米能级和介质层厚度对波导近红外波段可调谐传输特性的影响。为了提高调制性能，采用了多个晶胞（石墨烯-Al 2 O3）结构。结果表明，随着单胞周期数的增加，传播特性的调制深度明显增加。例如，如果费米能级在0.1- 0.5eV的范围内变化，则传播长度的调制深度可以达到约80%。随着频率的增加，混合模的有效折射率增加，而传播长度出现一个峰值。研究结果对于理解石墨烯等离子体器件的可调谐机制和设计新型波导结构，如谐振器和调制器等具有重要意义。
By integrating the graphene layer with the dielectric loaded surface plasmon waveguides, the tunable propagation properties have been investigated in the near-IR region, including the influences of operation frequency, the Fermi level of the graphene layer, and dielectric layer thickness. To improve the modulation properties, multiple unit cell (graphene-Al2O3) structure has been adopted. The results manifest that as the period number of the unit cell increases, the modulation depths of the propagation properties increase obviously. For instance, the modulation depth of propagation length can reach about 80% if the Fermi level changes in the range of 0.1–0.5 eV. As frequency increases, the effective index of the hybrid mode increases, while the propagation length shows a peak. The results are very helpful in understanding the tunable mechanisms of graphene plasmonic devices and designing novel waveguide structures, e.g. resonators and modulators.