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Multiplex Chemical Imaging Based on Broadband Stimulated Raman Scattering Microscopy
Published on: July 25, 2022
Multi-port beam combination and cleanup in large multimode fiber using stimulated Raman scattering
Optics Express
|June 17, 2009
Summary
Researchers combined four laser beams using stimulated Raman scattering (SRS) and a fiber combiner. SRS beam cleanup improved beam quality, achieving an M(2) better than 2 over long fiber lengths.
Area of Science:
- Optics and Photonics
- Laser Physics
- Nonlinear Optics
Background:
- High-power fiber lasers are crucial for various applications.
- Combining multiple laser beams efficiently is a significant challenge.
- Stimulated Raman scattering (SRS) offers potential for beam combination and cleanup.
Purpose of the Study:
- To demonstrate the successful combination of four laser beams using SRS.
- To investigate SRS for laser beam cleanup and quality improvement.
- To evaluate the performance of SRS beam cleanup over extended fiber lengths.
Main Methods:
- Utilized a multi-port fiber combiner for laser beam aggregation.
- Employed a large multimode fiber for SRS generation and propagation.
- Investigated SRS beam cleanup with a single laser beam.
- Measured beam quality using the M(2) metric.
Main Results:
- Successfully combined four laser beams via SRS.
- Observed multiple Stokes orders in the output.
- Identified loss at longer wavelengths limiting higher-order Stokes transmission and conversion efficiency.
- Achieved an M(2) value better than 2 for SRS beam cleanup over 400-1400 meters of fiber.
Conclusions:
- SRS is a viable technique for combining and cleaning up laser beams in multimode fibers.
- Fiber length and wavelength-dependent losses impact SRS efficiency.
- Promising results for laser beam quality improvement using SRS in optical fibers.
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