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An all-optical modulation method in sub-micron scale.

ABSTRACT: We report a theoretical study showing that by utilizing the illumination of an external laser, the Surface Plasmon Polaritons (SPP) signals on the graphene sheet can be modulated in the sub-micron scale. The SPP wave can propagate along the graphene in the middle infrared range when the graphene is properly doped. Graphene's carrier density can be modified by a visible laser when the graphene sheet is exfoliated on the hydrophilic SiO2/Si substrate, which yields an all-optical way to control the graphene's doping level. Consequently, the external laser beam can control the propagation of the graphene SPP between the ON and OFF status. This all-optical modulation effect is still obvious when the spot size of the external laser is reduced to 400 nm while the modulation depth is as high as 114.7 dB/μm.

SUBMITTER: Yang L

PROVIDER: S-EPMC4361842 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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An all-optical modulation method in sub-micron scale.

Yang Longzhi L Pei Chongyang C Shen Ao A Zhao Changyun C Li Yan Y Li Xia X Yu Hui H Li Yubo Y Jiang Xiaoqing X Yang Jianyi J

Scientific reports 20150317

We report a theoretical study showing that by utilizing the illumination of an external laser, the Surface Plasmon Polaritons (SPP) signals on the graphene sheet can be modulated in the sub-micron scale. The SPP wave can propagate along the graphene in the middle infrared range when the graphene is properly doped. Graphene's carrier density can be modified by a visible laser when the graphene sheet is exfoliated on the hydrophilic SiO2/Si substrate, which yields an all-optical way to control the ...[more]

PMID: 25777581

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