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Generation and Coherent Control of Pulsed Quantum Frequency Combs
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All-fibre heterogeneously-integrated frequency comb generation using silicon core fibre
Ronit Sohanpal1, Haonan Ren2,3, Li Shen4
1Optical Networks Group, Department of Electronic and Electrical Engineering, University College London, London, UK. ronit.sohanpal.14@ucl.ac.uk.
Nature Communications
|July 9, 2022
Summary
Researchers developed a compact, all-fibre optical frequency comb source. This silicon core fiber device offers a flat spectrum and high power for telecommunications and spectroscopy applications.
Area of Science:
- Photonics and Optical Engineering
- Materials Science
- Telecommunications
Background:
- Optical frequency combs (OFCs), initially for metrology, are expanding into optical communications, spectroscopy, and signal processing.
- Emerging applications demand compact, temperature-stable OFC sources with flat spectra, high per-tone power, narrow linewidth, and high optical signal-to-noise ratio (OSNR).
Purpose of the Study:
- To report the generation of a flat, high-power optical frequency comb in the telecom band.
- To demonstrate a compact, all-fibre, cavity-free OFC source suitable for demanding applications.
Main Methods:
- Utilized a 17 mm fully-integrated silicon core fiber as a parametric mixer.
- Employed an all-fibre, cavity-free design combining planar waveguide benefits with fiber platform advantages.
Main Results:
- Generated a 30 nm bandwidth frequency comb source containing 143 tones.
- Achieved a spectral flatness of 12 dB across the entire region.
- Demonstrated a linewidth of less than 3 kHz and an optical signal-to-noise ratio (OSNR) greater than 30 dB.
Conclusions:
- The developed silicon core fiber OFC source meets critical application demands for compactness and spectral quality.
- This all-fibre, cavity-free approach offers a promising solution for advanced optical communications and spectroscopy.
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