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Mutual coherence of two coupled multiline continuous-wave HF lasers.
Optics Letters
|September 11, 2009
Summary
Two coupled continuous-wave hydrogen fluoride (HF) lasers demonstrated complete mutual coherence. Stable laser coupling was achieved without precise resonator length adjustments, simplifying laser system design.
Area of Science:
- Optics and Photonics
- Laser Physics
Background:
- Continuous-wave (cw) hydrogen fluoride (HF) lasers are valuable tools in chemical physics and spectroscopy.
- Achieving stable and coherent coupling between multiple laser systems is crucial for advanced applications.
- Unstable resonators offer unique beam characteristics but can present challenges in mode control and coupling.
Purpose of the Study:
- To investigate the mutual coherence of two coupled multiline cw HF lasers.
- To determine the conditions necessary for stable coupling between such laser systems.
- To assess the impact of resonator design on laser beam coherence.
Main Methods:
- Two multiline cw HF lasers with unstable resonators were utilized.
- 20% of each laser's output was injected into the other laser for coupling.
- Mutual coherence was quantified by measuring the visibility (V) of interference fringes generated by overlapping the output beams.
Main Results:
- Both single-line and multiline interference patterns were observed, indicating successful interference.
- Complete coupling between the two laser outputs was achieved with 20% injection.
- Stable coupling was demonstrated without the need for critical adjustments to individual laser resonator lengths.
Conclusions:
- Stable and coherent coupling of multiline cw HF lasers is achievable.
- The demonstrated coupling method is robust and not overly sensitive to resonator length tuning.
- This work simplifies the setup for coherent combination of HF laser outputs, potentially enabling new applications.
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