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Abstract Dual-comb interferometry harnesses the interference of two laser frequency combs to provide unprecedented capability in spectroscopy applications. In the past decade, the state-of-the-art systems have reached a point where the signal-to-noise ratio per unit acquisition time is fundamentally limited by shot noise from vacuum fluctuations. To address the issue, we propose an entanglement-enhanced dual-comb spectroscopy protocol that leverages quantum resources to significantly improve the signal-to-noise ratio performance. To analyze the performance of real systems, we develop a quantum model of dual-comb spectroscopy that takes practical noises into consideration. Based on this model, we propose quantum combs with side-band entanglement around each comb lines to suppress the shot noise in heterodyne detection. Our results show significant quantum advantages in the uW to mW power range, making this technique particularly attractive for biological and chemical sensing applications. Furthermore, the quantum comb can be engineered using nonlinear optics and promises near-term experimentation.
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Elastic tape behavior of a bi-directional Kerr-lens mode-locked dual-comb ring laser
We experimentally investigate a fixed point of a bi-directional dual-comb ring laser and the behavior of dual-comb signals in different spectral regions. We show that the results are quite different from those obtained with traditional dual-comb spectroscopy. We explain the difference using the elastic tape formalism that we apply to a bi-directional ring laser. We also discuss how the results can aid efforts to synchronize two bi-directional laser systems to enable rapid and high-resolution multidimensional coherent spectroscopy with a compact apparatus.
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- Award ID(s):
- 1904704
- PAR ID:
- 10134758
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Letters
- Volume:
- 45
- Issue:
- 5
- ISSN:
- 0146-9592; OPLEDP
- Format(s):
- Medium: X Size: Article No. 1080
- Size(s):
- Article No. 1080
- Sponsoring Org:
- National Science Foundation
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