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arXiv · 2405.03182

Reference-free dual-comb spectroscopy with inbuilt coherence

Mikhail Roiz·Santeri Larnimaa·Touko Uotila·Mikko Narhi·Markku Vainio
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Abstract

We demonstrate a simple system for dual-comb spectroscopy based on two inherently coherent optical frequency combs generated via seeded parametric down-conversion. The inbuilt coherence is established by making the two combs share a common comb line. We show that the inbuilt coherence makes it possible to use a simple numerical post-processing procedure to compensate for small drifts of the dual-comb interferogram arrival-time and phase. This enables long-time coherent averaging of the interferograms.

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Mikhail Roiz, Santeri Larnimaa, Touko Uotila, Mikko Narhi, Markku Vainio. 2024-05-06. Reference-free dual-comb spectroscopy with inbuilt coherence. https://arxiv.org/abs/2405.03182

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