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Excitation of surface electromagnetic waves in a graphene-based Bragg grating.

ABSTRACT: Here, we report the fabrication of a graphene-based Bragg grating (one-dimensional photonic crystal) and experimentally demonstrate the excitation of surface electromagnetic waves in the periodic structure using prism coupling technique. Surface electromagnetic waves are non-radiative electromagnetic modes that appear on the surface of semi-infinite 1D photonic crystal. In order to fabricate the graphene-based Bragg grating, alternating layers of high (graphene) and low (PMMA) refractive index materials have been used. The reflectivity plot shows a deepest, narrow dip after total internal reflection angle corresponds to the surface electromagnetic mode propagating at the Bragg grating/air boundary. The proposed graphene based Bragg grating can find a variety of potential surface electromagnetic wave applications such as sensors, fluorescence emission enhancement, modulators, etc.

SUBMITTER: Sreekanth KV

PROVIDER: S-EPMC3471096 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Excitation of surface electromagnetic waves in a graphene-based Bragg grating.

Sreekanth Kandammathe Valiyaveedu KV Zeng Shuwen S Shang Jingzhi J Yong Ken-Tye KT Yu Ting T

Scientific reports 20121015

Here, we report the fabrication of a graphene-based Bragg grating (one-dimensional photonic crystal) and experimentally demonstrate the excitation of surface electromagnetic waves in the periodic structure using prism coupling technique. Surface electromagnetic waves are non-radiative electromagnetic modes that appear on the surface of semi-infinite 1D photonic crystal. In order to fabricate the graphene-based Bragg grating, alternating layers of high (graphene) and low (PMMA) refractive index m ...[more]

PMID: 23071901

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