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Erbium-doped-fiber-based broad visible range frequency comb with a 30 GHz mode spacing for astronomical applications
Optics Express
|June 29, 2023
Summary
Researchers developed a novel optical frequency comb with a 30 GHz mode spacing and broad visible spectrum coverage. This stable comb system is ideal for astronomical observations and exoplanet detection.
Area of Science:
- Optics and Photonics
- Astronomy
- Physics
Background:
- Optical frequency combs are crucial for high-precision measurements.
- Existing combs often lack broad spectral coverage or wide mode spacing.
- Applications in astronomy require combs with specific characteristics for advanced observations.
Purpose of the Study:
- To develop a novel optical frequency comb with a 30 GHz mode spacing.
- To achieve broad wavelength coverage in the visible spectrum.
- To demonstrate the long-term stability of the generated comb spectrum.
Main Methods:
- Utilized an erbium-doped-fiber-based femtosecond laser.
- Implemented mode filtering using newly designed optical cavities.
- Generated a broadband visible-range comb using a chirped periodically-poled lithium niobate ridge waveguide.
Main Results:
- Achieved a 30 GHz mode spacing.
- Obtained 62% available wavelength coverage in the visible region.
- Demonstrated nearly 40 dB spectral contrast.
- Showcased spectral stability with minimal change over 29 months.
Conclusions:
- The developed optical frequency comb offers significant advantages for specialized applications.
- Its broad spectral coverage and wide mode spacing are beneficial for astronomical observations.
- The comb's stability supports its use in demanding scientific investigations, including exoplanet exploration and cosmology.
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