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Related Experiment Video

Updated: May 14, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

Improved multi-channel multi-carrier generation using gain-independent multi-channel frequency shifting recirculating

Junwen Zhang¹, Jianjun Yu, Nan Chi

¹Department of Communication Science and Engineering, Fudan University, Shanghai 200433, China.

|February 8, 2013

Summary

This study introduces a novel method for generating stable, frequency-locked optical multi-carriers using a recirculating frequency shifter loop. The improved scheme efficiently produces multiple subcarriers per channel, ideal for advanced optical communication systems.

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Area of Science:

Photonics
Optical Communications
Signal Processing

Background:

Generating stable optical frequency-locked multi-channel multi-carriers (MCMC) is crucial for advanced WDM systems.
Existing methods may face limitations in stability and channel density.

Purpose of the Study:

To propose and demonstrate an improved scheme for generating optical frequency-locked MCMC.
To enhance the performance of recirculating frequency shifter (RFS) loops for MCMC generation.

Main Methods:

Utilizing a gain-independent multi-channel recirculating frequency shifter (MC-RFS) loop.
Employing single sideband (SSB) modulation within the MC-RFS loop.
Rebuilding the RFS structure for improved performance and stability.

Main Results:

Successfully generated N-channel subcarriers per round trip without interference.
Demonstrated a dual-channel RFS loop experiment producing 62 frequency-locked subcarriers.
Achieved 25-GHz frequency spacing with 31 tones per channel in a dual-carrier setup.

Conclusions:

The proposed MC-RFS loop scheme effectively generates stable, frequency-locked MCMC.
This method offers a robust solution for creating multi-channel WDM sources.
The improved RFS structure enhances the efficiency and performance of MCMC generation.