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Long-term stable mode locking of a visible diode laser with phase-conjugate feedback
Optics Letters
|October 28, 2009
Summary
Researchers developed a new method for stable phase-conjugate feedback (pcf) in semiconductor lasers. This technique enhances laser stability and performance, achieving ~30 ps pulse widths and <2 ps timing jitter.
Area of Science:
- Optics and Photonics
- Semiconductor Lasers
- Nonlinear Optics
Background:
- Mode-locked semiconductor lasers are crucial for various applications.
- Achieving stable phase-conjugate feedback (pcf) has been a challenge.
- Photorefractive crystals offer potential for optical feedback mechanisms.
Purpose of the Study:
- To develop a novel method for achieving long-term stable pcf in mode-locked semiconductor lasers.
- To investigate the underlying mechanisms responsible for the enhanced stability.
- To demonstrate improved laser performance using the new pcf technique.
Main Methods:
- Utilized a barium titanate crystal as a self-pumped phase-conjugate mirror.
- Employed a visible, antireflection-coated AlGaInP diode laser.
- Implemented a new dynamic writing procedure for index grating growth in the photorefractive crystal.
Main Results:
- Achieved long-term stable phase-conjugate feedback (pcf).
- Demonstrated stable mode-locked operation with ~30 picosecond pulse widths.
- Recorded a timing jitter of less than 2 picoseconds.
Conclusions:
- The novel dynamic writing procedure significantly enhances the stability of pcf.
- This method overcomes limitations of previous approaches for stable pcf.
- The technique enables robust and high-performance mode-locked semiconductor lasers.
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