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Fabrication of a Low-Cost, Fiber-Coupled, and Air-Spaced Fabry-Pérot Etalon
Published on: February 3, 2023
Conjugate Fabry-Perot cavity pair for improved astro-comb accuracy
Chih-Hao Li1, Guoqing Chang, Alexander G Glenday
1Harvard-Smithsonian Center for Astrophysics, Harvard University, Cambridge, Massachusetts 02138, USA. chli@cfa.harvard.edu
Optics Letters
|August 4, 2012
Summary
A new conjugate Fabry-Perot cavity pair filtering scheme enhances astronomical comb (astro-comb) spectral line accuracy. This method improves robustness against systematic errors from nonlinear optical fiber processes.
Area of Science:
- Astronomy
- Optical Physics
- Spectroscopy
Background:
- Astronomical spectrographs require precise spectral calibration.
- Optical frequency combs (astro-combs) offer high-precision calibration but are susceptible to nonlinear fiber effects.
- Systematic errors can limit the accuracy of astro-comb spectral lines.
Purpose of the Study:
- To introduce a novel mode-filtering scheme for astro-combs.
- To enhance the robustness of astro-comb spectral line accuracy against nonlinearities.
- To mitigate systematic errors in astronomical spectroscopy.
Main Methods:
- Proposed a new filtering scheme using two Fabry-Perot cavities (conjugate Fabry-Perot cavity pair).
- Conducted simulations to evaluate the filtering scheme's performance.
- Assessed the scheme's effectiveness against systematic errors from nonlinear optical fibers.
Main Results:
- The conjugate Fabry-Perot cavity pair scheme significantly improves astro-comb spectral line accuracy.
- The filtering scheme demonstrates increased robustness against nonlinear processes.
- Simulations confirm reduced systematic errors in spectral line calibration.
Conclusions:
- The proposed conjugate Fabry-Perot cavity pair is an effective solution for enhancing astro-comb stability.
- This method offers a pathway to more accurate astronomical measurements.
- The scheme addresses a critical challenge in high-precision astronomical spectroscopy.
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