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arXiv · 1202.4791

High-speed waveguide-coupled graphene-on-graphene optical modulators

Steven J. Koester·Mo Li
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Abstract

An electro-absorption optical modulator concept based upon a dual-graphene layer is presented. The device consists of a silicon-on-insulator waveguide upon which two graphene layers reside, separated by a thin insulating region. The lower graphene acts as a tunable absorber, while the upper layer functions as a transparent gate electrode. Calculations based upon realistic graphene material properties show that 3-dB bandwidths over 100 GHz (30 GHz) are possible at near- (\lambda=1.55 \mu m) and mid- (\lambda=3.5\mu m) infrared bands. The effect of background doping and potential fluctuations on the bandwidth, modulation depth and insertion loss are also quantified.

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Steven J. Koester, Mo Li. 2012-02-21. High-speed waveguide-coupled graphene-on-graphene optical modulators. https://doi.org/10.1063/1.4704663

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