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Updated: Aug 10, 2026

Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
A frequency-modulated quantum-cascade laser for spectroscopy of CH4 and N2O isotopomers
Gianluca Gagliardi1, Simone Borri, Filippo Tamassia
1Istituto Nazionale di Ottica Applicata, Comprensorio A.Olivetti, Via Campi Flegrei 34, 80078, Pozzuoli Naples, Italy. gagliardi@inoa.it
Abstract:
We report the development of a novel laser spectrometer for high-sensitivity detection of methane and nitrous oxide. The system relies on a quantum-cascade laser source emitting wavelength of around 8.06 microm, where strong fundamental absorption bands occur for the considered species and their isotopomers. The detection technique is based on audio-frequency and radio-frequency modulation of laser radiation. First experimental tests have been performed to estimate the achievable detection limits and the signal reproducibility levels in view of possible measurements of (13)C/(12)C, (18)O/(16)O, (17)O/(16)O and (15)N/(14)N isotope ratios.
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