David P. Long

PRECISION CAVITY-ENHANCED DUAL-COMB SPECTROSCOPY: APPLICATION TO THE GAS METROLOGY OF CO2, H2O, and N2O.

With inherent simplicity, mutual phase coherence, and a high degree of user control, electro-optic frequency combs are amenable to both dual-comb spectroscopya and cavity-enhanced comb spectroscopy.b This combination of fast, multiplexed spectroscopy, with an effective absorption pathlength >1 km, is used here to perform line-by-line metrology of the gas-phase absorption spectra of CO2, H2O, and N2O in the near-infrared. We report absolute transition frequency with precision better than 1 MHz in 1 s of spectral acquisition per transition using a comb with an instantaneous optical bandwidth of 6 GHz, tunable over the entire 6240-6370 cm−1range. A full model for the electric field transmitted through the enhancement cavity (even in the presence of strong molecular absorption and dispersion) will be discussed.

PHOTOACOUSTIC SPECTROSCOPY OF PRESSURE- AND TEMPERATURE- DEPENDENCE IN THE O2 A-BAND

MATTHEW J. CICH, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA; ELIZABETH M LUNNY, GAUTAM STROSCIO, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA; THINH QUOC BUI, JILA, National Institute of Standards and Technology and Univ. of Colorado Department of Physics, University of Colorado, Boulder, Boulder, CO, USA; PRIYANKA RUPASINGHE, Physical Sciences, Cameron University, Lawton, OK, USA; DANIEL HOGAN, Department of Applied Physics, Stanford University, Stanford, CA, USA; CAITLIN BRAY, Department of Chemistry, Wesleyan University, Middletown, CT, USA; DAVID A. LONG, JOSEPH T. HODGES, Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA; TIMOTHY J. CRAWFORD, CHARLES MILLER, BRIAN DROUIN, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA; MITCHIO OKUMURA, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, USA.