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Published on: March 19, 2016
Silicon waveguide modulator based on carrier depletion in periodically interleaved PN junctions
Zhi-Yong Li1, Dan-Xia Xu, W Ross McKinnon
1Institute of Semiconductors (IS), Chinese Academy of Sciences (CAS), 35A Tsinghua East Road, Beijing 100083, China. lizhy@semi.ac.cn
Optics Express
|September 3, 2009
Summary
We designed a silicon waveguide modulator using interleaved PN junctions for enhanced light interaction. This device achieves high modulation efficiency and a wide frequency bandwidth, promising advancements in optical communication.
Area of Science:
- Photonics
- Integrated Optics
- Semiconductor Devices
Background:
- Silicon photonics is crucial for high-speed optical communication.
- Waveguide modulators are key components in optical systems.
- Carrier depletion modulators offer efficient modulation.
Purpose of the Study:
- To design and simulate a novel silicon waveguide modulator.
- To improve modulator performance through optimized PN junction geometry.
- To achieve high modulation efficiency and bandwidth.
Main Methods:
- Numerical simulations of a silicon waveguide modulator.
- Design based on carrier depletion in periodically interleaved PN junctions.
- Analysis of optical mode overlap and depletion region interaction.
Main Results:
- High modulation efficiency of 0.56 V x cm at 3 V bias.
- 3 dB frequency bandwidth exceeding 40 GHz.
- Device length of 1.86 mm with a maximum intrinsic loss of 4.3 dB.
Conclusions:
- The proposed modulator design offers superior performance compared to conventional designs.
- Optimized PN junction orientation significantly enhances optical mode overlap.
- This device shows potential for next-generation high-speed optical communication systems.
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