A frequency-modulated quantum-cascade laser for spectroscopy of CH4 and N2O isotopomers.
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.
Istituto Nazionale di Ottica Applicata, Comprensorio A.Olivetti, Via Campi Flegrei 34, 80078, Pozzuoli Naples, Italy. gagliardi@inoa.it
Gianluca
G
Gagliardi
Simone
S
Borri
Filippo
F
Tamassia
Federico
F
Capasso
Claire
C
Gmachl
Deborah L
DL
Sivco
James N
JN
Baillargeon
Albert L
AL
Hutchinson
Alfred Y
AY
Cho
D002247:Carbon Isotopes / Q000032:analysis*; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods*; D007834:Lasers; D008697:Methane / Q000032:analysis* / Q000737:chemistry; D009587:Nitrogen Isotopes / Q000032:analysis*; D009609:Nitrous Oxide / Q000032:analysis* / Q000737:chemistry; D010103:Oxygen Isotopes / Q000032:analysis*; D013055:Spectrophotometry, Infrared / Q000295:instrumentation / Q000379:methods*
D002247:Carbon Isotopes; D009587:Nitrogen Isotopes; D010103:Oxygen Isotopes; D009609:Nitrous Oxide; D008697:Methane