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arXiv · 1809.07150

Mid-infrared GeSn Electro-Absorption Optical Modulators on Silicon

Jun-Han Lin·Bo-Jun Huang·H. H. Cheng·Guo-En Chang
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Abstract

Mid-infrared silicon photonics has recently emerged as a new technology for a wide range of applications such as optical communication, lidar, and bio-sensing. One key component enabling this technology is the mid-infrared optical modulator used for encoding optical signals. Here, we present a GeSn electro-absorption modulator that can operate in the mid-infrared range. Importantly, this device is monolithically integrated on a silicon substrate, which provides compatibility with standard complementary metal-oxide-semiconductor technology for scalable manufacturing. By alloying Ge with Sn to engineer the bandgap, we observed a clear Franz-Keldysh effect and achieved optimal modulation in the mid-infrared range of 2067-2208 nm with a maximum absorption ratio of 1.8. The results on the Si-based mid-infrared optical modulator open a new avenue for next-generation mid-infrared silicon photonics.

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Jun-Han Lin, Bo-Jun Huang, H. H. Cheng, Guo-En Chang. 2018-08-25. Mid-infrared GeSn Electro-Absorption Optical Modulators on Silicon. https://arxiv.org/abs/1809.07150

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