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arXiv · 1905.00647

Room-Temperature Continuous-Wave Frequency-Referenced Spectrometer up to 7.5 THz

Michele De Regis·Saverio Bartalini·Marco Ravaro·Davide Calonico·Paolo De Natale·Luigi Consolino
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Abstract

The lack of coherent room-temperature sources in the whole terahertz spectral window (0.3-10 THz) has significantly hampered the growth of scientific and technological applications in this range. Among them, high-precision frequency measurements of molecular transitions play a central role but remain an open challenge. Here, room-temperature generation and detection of continuous-wave, broadly tunable, narrow-linewidth THz radiation are presented, and their application to high-resolution spectroscopy in the broad 1-7.5 THz spectral range is demonstrated. This result has been achieved by implementing a Cherenkov phase-matching scheme into a channel waveguide in a nonlinear crystal. This simple approach, entirely based on robust telecom technology, unprecedently merges in a single source an ultra-broad continuous-wave spectral coverage and a state-of-the-art accuracy (approximately 10-9) in molecular-transition-center determination.

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Michele De Regis, Saverio Bartalini, Marco Ravaro, Davide Calonico, Paolo De Natale, Luigi Consolino. 2019-05-02. Room-Temperature Continuous-Wave Frequency-Referenced Spectrometer up to 7.5 THz. https://doi.org/10.1103/physrevapplied.10.064041

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