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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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Multilevel quadrature amplitude multiplexing using coherently coupled orbital angular momentum modes
Optics Express
|May 3, 2018
Summary
This study demonstrates high-speed data transmission using spatial light modes, achieving significant spectral efficiency gains. The novel method encodes data onto twisted light, enabling faster communication links.
Area of Science:
- Optical communications
- Photonics
- Information theory
Background:
- Spectral efficiency is crucial for modern communication systems.
- Spatial light modes offer a platform for enhanced information encoding.
- Current limitations include switching speed and detection methods for spatial mode-based links.
Purpose of the Study:
- To demonstrate high-speed capabilities in spatial light mode communication.
- To increase spectral efficiency by encoding information onto coherently coupled spatial modes.
- To validate signal recovery below forward error correction limits.
Main Methods:
- Coherent coupling of twisted light modes using passive optical elements and electro-optical modulators.
- Encoding and detection of two coherently coupled modes with 0.5 Gbaud quadrature amplitude modulation (16- and 32-QAM) signals.
- Utilizing both phase and amplitude of coupled modes for data encoding.
Main Results:
- Achieved a 4X and 5X increase in spectral efficiency.
- Successfully recovered signals with error rates below the forward error correction limit.
- Demonstrated high-speed switching and detection capabilities.
Conclusions:
- The developed system shows high-speed potential for spatial mode-based optical communication.
- Passive optical techniques enable robust signal recovery.
- The data rate is hardware-limited, with potential for multi-Gigahertz operation.
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