Versatile mid-infrared frequency-comb referenced sub-Doppler spectrometer
Authors: Gambetta A., Vicentini E., Coluccelli N., Wang Y., Fernandez TT., Maddaloni P., De Natale P., Castrillo A., Gianfrani L., Laporta P., Galzerano G.
Autors Affiliation: Dipartimento di Fisica-Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy; Istituto di Fotonica e Nanotecnologie-CNR, Piazza Leonardo da Vinci 32, 20133 Milano, Italy; CNR-INO, Istituto Nazionale di Ottica, Via Campi Flegrei 34, 80078 Pozzuoli (NA), Italy; INFN, Istituto Nazionale di Fisica Nucleare, Sez. di Napoli, Complesso Universitario di M. S. Angelo, Via Cintia, 80126 Napoli, Italy; CNR-INO, Istituto Nazionale di Ottica, Largo Enrico Fermi 6, 50125 Firenze, Italy; Dipartimento di Matematica e Fisica-Universit`a degli Studi della Campania
“Luigi Vanvitelli,” Viale Lincoln 5, 81100 Caserta, Italy
Abstract: We present a mid-IR high-precision spectrometer capable of performing accurate Doppler-free measurements with absolute calibration of the optical axis and high signal-to-noise ratio. The system is based on a widely tunable mid-IR offset-free frequency comb and a Quantum-Cascade-Laser (QCL). The QCL emission frequency is offset locked to one of the comb teeth to provide absolute-frequency calibration, spectral-narrowing, and accurate fine frequency tuning. Both the comb repetition frequency and QCL-comb offset frequency can be modulated to provide, respectively, slow- and fast-frequency-calibrated scanning capabilities. The characterisation of the spectrometer is demonstrated by recording sub-Doppler saturated absorption features of the CHF3 molecule at around 8.6 micron with a maximum signal-to-noise ratio of 7e103 in 10 s integration time, frequency-resolution of 160 kHz, and accuracy of less than 10 kHz.
Journal/Review: APL PHOTONICS
Volume: 3 (4) Pages from: 046103-1 to: 046103-9
More Information: – The authors acknowledge financial support from the Italian Ministry of University and Research, FIRB Project No. RBFR1006TZ, and ELI Nuclear Physics (ELI-NP) infrastructure.KeyWords: Calibration; Quantum cascade lasers; Spectrometers, Absolute calibration; Emission frequency; Frequency resolutions; High signal-to-noise ratio; Mid-infrared frequency combs; Repetition frequency; Saturated absorptions; Spectral narrowing, Signal to noise ratio; optical frequency comb; fluoroformDOI: 10.1063/1.5025135Citations: 3data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2020-10-18References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here