0000000000703889
AUTHOR
G. Fanjoux
Génération de supercontinuum par cascade de mélanges à quatre ondes intermodaux dans une fibre optique multimode à saut d'indice
International audience
Line Coupling Effects in Anisotropic Raman Q-Branches of the ν1/2ν2 Fermi Dyad in CO2
0021-9606; The generalized energy corrected sudden model is used to calculate the Q branch of the anisotropic coherent anti-Stokes Raman scattering spectra corresponding to the v1 and 2v2 transitions of the Fermi dyad of CO2. The corresponding experimental spectra have been recorded for pressures leading to a consistent overlapping between the rotational components. This leads to a new experimental evaluation of the relaxation time of the second-order tensor associated with the rotational angular momentum. The value is in excellent agreement with that already obtained from the study of the infrared absorption Q branch, the Rayleigh scattering, and the viscomagnetic effect. (C) 1995 American…
Study of Collisional Effects on Band Shapes of the ν1/2ν2 Fermi Dyad in CO2 Gas with Stimulated Raman-Spectroscopy .3. Modeling of Collisional Narrowing and Study of Vibrational Shifting and Broadening at High-Temperature
0021-9606; High resolution stimulated Raman spectra (SRS) of the ν1/2ν2 Fermi dyad of CO2 have been recorded in the 0.4-22. amagat density range at 700 K and in the 0.6-16 amagat density range at 900 K. The data have been successfully analyzed with a theoretical model taking into account both rotational line mixing through the energy corrected sudden-polynomial (ECS-P) law for the relaxation matrix and vibrational line broadening gamma(v) and line shifting delta(v). The two vibrational parameters have been accurately determined from fit to the experimental spectra. These new high temperature data together with previous data obtained at 295 and 500 K [B. Lavorel et al., J. Chem. Phys. 93, 21…
Determination of Temperature by Stimulated Raman Scattering of Molecular Nitrogen, Oxygen, and Carbon-Dioxide
0721-7269; We have determined the temperature from SRS spectra of N2-N2, N2-CO2, O2-O2, and CO2-CO2 recorded in wide pressure and temperature ranges. The fitting procedure takes simultaneously into account the Dicke effect and motional narrowing. We have quantified the accuracy of the MEG and ECS-P models for rotational relaxation. The temperature extracted from each model is compared with thermocouple measurements. The influence of vibrational broadening and shifting is discussed in detail.
Fitting and scaling laws for high temperature Q branch collapse in the O2 stimulated Raman spectra in O2-H2O mixtures
0021-9606