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Quasi-light Storage for Optical Data Packets
Published on: February 6, 2014
50-Gb/s silicon quadrature phase-shift keying modulator
Po Dong1, Long Chen, Chongjin Xie
1Bell Labs, Alcatel-Lucent, 791 Holmdel Road, Holmdel, NJ 07733, USA. po.dong@alcatel-lucent.com
Optics Express
|October 6, 2012
Summary
We demonstrated quadrature phase-shift keying (QPSK) modulation using silicon Mach-Zehnder modulators. This breakthrough enables high-speed coherent optical communications on a powerful silicon photonics platform.
Area of Science:
- Photonics and Optical Communications
- Integrated Circuits
- Digital Modulation Techniques
Background:
- Coherent optical communications require advanced modulation formats for high data rates.
- Silicon photonics offers a promising platform for miniaturized and cost-effective optical components.
- Mach-Zehnder modulators are key devices for optical signal manipulation.
Purpose of the Study:
- To demonstrate quadrature phase-shift keying (QPSK) modulation using silicon Mach-Zehnder modulators.
- To evaluate the performance of silicon photonics in high-speed coherent optical systems.
- To assess the feasibility of silicon photonics for future optical communication networks.
Main Methods:
- Utilized two nested silicon Mach-Zehnder modulators for QPSK signal generation.
- Generated a 50-Gb/s QPSK signal.
- Measured optical signal-to-noise ratio (OSNR) penalties at a bit-error ratio (BER) of 10(-3).
Main Results:
- Achieved the first successful demonstration of QPSK modulation with silicon Mach-Zehnder modulators.
- Generated a 50-Gb/s QPSK signal with minimal OSNR penalties (2.7 dB) from the theoretical limit.
- Demonstrated high-performance modulation suitable for coherent optical communications.
Conclusions:
- Silicon photonics is a viable and powerful platform for photonic integrated circuits.
- The demonstrated QPSK modulation validates the potential of silicon photonics for advanced coherent optical communications.
- This work paves the way for high-capacity, compact optical transceivers.
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