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Author Spotlight: Fabrication of a Low-Cost, Fiber-Coupled, and Air-Spaced Fabry-Pérot Etalon
Published on: February 3, 2023
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Visible astro-comb filtered by a passively stabilized Fabry-Perot cavity.
Yuxuan Ma1, Fei Meng1, Yizhou Liu1
1State Key Laboratory of Advanced Optical Communication System and Networks, School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, China.
The Review of Scientific Instruments
|February 3, 2019
Summary
We developed a compact visible astro-comb for astronomical spectroscopy. This tool provides stable, high-precision frequency measurements across the 560-700 nm spectrum.
Area of Science:
- Astronomy
- Optical Physics
- Spectroscopy
Background:
- Astronomical spectroscopy requires precise frequency references.
- Existing tools may lack the required stability or spectral coverage.
Purpose of the Study:
- To demonstrate a compact visible astro-comb for astronomical spectroscopy.
- To achieve high frequency stability and spectral coverage in the visible range.
Main Methods:
- Utilized a Ytterbium (Yb):fiber laser frequency comb as a seed source, phase-locked to a Rubidium (Rb) clock.
- Generated a visible super-continuum and filtered comb teeth using a Fabry-Perot cavity with custom chirped mirrors.
- Resolved filtered comb teeth using an astronomical spectrograph with R=49,000 resolution.
Main Results:
- Demonstrated a compact 29.3 GHz visible astro-comb spanning 560 nm to 700 nm.
- Achieved high frequency stability and side mode suppression ratio from the seed comb.
- Observed sharp line shapes, zero noise floor, and uniform exposure amplitude for filtered comb teeth.
Conclusions:
- The developed visible astro-comb is suitable for high-precision astronomical spectroscopy.
- The compact design and stable performance offer advantages for astrophysical observations.
- This technology enables enhanced spectral analysis in visible astronomy.
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