摘要
构建了一种含双支节结构的石墨烯/介质/石墨烯亚波长波导结构。该结构将支节结构的选频特性和石墨烯的电可调特性相结合,能够实现在可见光到中红外范围内对入射光光强的动态调制。表面等离激元将光能量局限在纳米尺度的介质狭缝中,使调制器突破衍射极限,并且增强了石墨烯与光的相互作用。利用有限元法分析了石墨烯的化学势、支节长度以及介质材料对波导结构输出光强的影响。仿真结果表明:当入射波长为1550nm、支节长度为315nm、化学势由0.80eV下降到0.78eV时,消光比可达到6.77dB。与传统调制器相比,所提光电调制器能够在保证高消光比的同时具有较高的调制效率,并且体积小、结构简单紧凑,可满足大规模集成应用的要求。
A graphene/dielectric/graphene sub-wavelength waveguide structure with double branched structure is constructed.The frequency-selection characteristic of branch structure is combined with the electrical tunable characteristic of graphene,and the dynamic modulation of the intensity of incident light from visible light to midinfrared can be achieved.Surface plasmon polaritons keep the light energy within the nanoscale dielectric slit,which causes the modulator to break the diffraction limit and enhance the interaction between graphene and light.Effects of the chemical potential,branch length and dielectric material of graphene on the output light intensity of the waveguide structure are analyzed by finite element method.Simulation results indicate that,when the incident light wavelength is 1550 nm,the branch length is 315 nm and the chemical potential decreases from 0.80 eV to 0.78 eV,the extinction ratio reaches 6.77 dB.Compared with the conventional modulator,the proposed photoelectric modulator can guarantee the high extinction ratio and modulation efficiency,and it is small in size and the structure is compact and simple,which can meet the requirements of large scale integration applications.
作者
李志全
冯丹丹
李欣
白兰迪
刘同磊
岳中
顾而丹
Li Zhiquan;Feng Dandan;Li Xin;Bai Landi;Liu Tonglei;Yue Zhong;Gu Erdan(Institute of Electrical Engineering, Yanshan University, Qinhuangdao, Hebei 066004, China;Institute of Mathematics and Information Technology, Hebei Normal University of Science ＆ Technology Qinhuangdao, Hebei 066004, China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2018年第1期290-297,共8页
Acta Optica Sinica
基金
河北省自然科学基金(F2017203316)
关键词
表面光学
表面等离激元
石墨烯
光电调制器
支节结构
optics at surfaces
surface plasmon polaritons
graphene
photoelectric modulator
branched structure
