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arXiv · 1402.7127

Multifunctional graphene optical modulator and photodetector integrated on silicon waveguides

Nathan Youngblood·Yoska Anugrah·Rui Ma·Steven J. Koester·Mo Li
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Abstract

For optical communication, information is converted between optical and electrical signal domains at a high rate. The devices to achieve such a conversion are various types of electro-optical modulators and photodetectors. These two types of optoelectronic devices, equally important, require different materials and consequently it has been challenging to realize both using a single material combination, especially in a way that can be integrated on the ubiquitous silicon platform. Graphene, with its gapless band structure, stands out as a unique optoelectronic material that allows both photodetection and optical modulation. Here, we demonstrate a single graphene-based device that simultaneously provides both efficient optical modulation and photodetection. The graphene device is integrated on a silicon waveguide and is tunable with a gate made from another layer of graphene to achieve near-infrared photodetection responsivity of 57 mA/W and modulation depth of 64%. This novel multifunctional device may lead to many unprecedented optoelectronic applications.

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Nathan Youngblood, Yoska Anugrah, Rui Ma, Steven J. Koester, Mo Li. 2014-02-28. Multifunctional graphene optical modulator and photodetector integrated on silicon waveguides. https://doi.org/10.1021/nl500712u

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