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High speed silicon Mach-Zehnder modulator based on interleaved PN junctions
1State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, P. O. Box 912, Beijing 100083, China.
Optics Express
|July 10, 2012
Summary
This study introduces a novel silicon Mach-Zehnder modulator using interleaved PN junctions. It achieves high modulation efficiency and low loss, enabling 40 Gbit/s operation.
Area of Science:
- Photonics and optoelectronics
- Semiconductor device physics
Background:
- Silicon photonics is crucial for high-speed optical communication.
- Mach-Zehnder modulators are key components, but often face trade-offs between efficiency, loss, and speed.
Purpose of the Study:
- To propose and demonstrate a novel silicon Mach-Zehnder modulator design.
- To achieve high modulation efficiency and low insertion loss simultaneously.
- To enable high-speed data transmission.
Main Methods:
- Utilized interleaved PN junctions in a silicon Mach-Zehnder modulator.
- Optimized doping concentration to 2 × 10^17 cm^-3.
- Fabricated a phase shifter of 750 μm length.
Main Results:
- Achieved a low V(π)L(π) of 1.5–2.0 V·cm, indicating high modulation efficiency.
- Demonstrated low doping-induced loss of approximately 10 dB/cm.
- Experimentally verified high-speed operation up to 40 Gbit/s.
- Obtained an extinction ratio of 7.01 dB.
Conclusions:
- The proposed interleaved PN junction design offers a promising solution for efficient and low-loss silicon Mach-Zehnder modulators.
- This device architecture facilitates high-speed optical modulation essential for modern communication systems.
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