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Raman amplification of recirculating pulses in a reentrant fiber loop
Optics Letters
|September 3, 2009
Summary
Researchers generated 130 optical pulses from one input pulse using a fiber loop and Raman amplification. This technique compensates for signal loss and bifurcation, enabling stable pulse generation.
Area of Science:
- Optics and Photonics
- Fiber Optics
- Nonlinear Optics
Background:
- Optical pulse generation is crucial for various applications.
- Maintaining pulse integrity over long distances and multiple cycles is challenging.
- Active reentrant fiber loops offer a potential platform for pulse manipulation.
Purpose of the Study:
- To demonstrate the generation of a high-repetition-rate optical pulse train.
- To investigate the use of Raman amplification for loss compensation in a fiber loop.
- To analyze the impact of pump power fluctuations on pulse stability.
Main Methods:
- Utilizing an 810-m single-mode fiber loop closed by a directional coupler.
- Employing Raman amplification with 1.064-microm pump pulses to counteract 1.12-microm signal loss.
- Recirculating a single input optical pulse within the active loop.
Main Results:
- Successfully generated a train of 130 optical pulses.
- Raman amplification effectively compensated for propagation loss and coupler bifurcation.
- Investigated and reported the effects of pump-power fluctuations on pulse amplitude stability and background noise.
Conclusions:
- The active reentrant fiber loop with Raman amplification is a viable method for generating high-density optical pulse trains.
- The system demonstrates effective compensation for signal degradation.
- Further studies can optimize pump power control for enhanced pulse quality.
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