Open AccessOn the possibility of simultaneous temperature, species, and electric field measurements by coupled hybrid fs/ps CARS and EFISHG
Author(s) -
Jonathan E. Retter,
Gregory S. Elliott
Publication year - 2019
Publication title -
applied optics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.668
H-Index - 197
eISSN - 2155-3165
pISSN - 1559-128X
DOI - 10.1364/ao.58.002557
Subject(s) - electric field , signal (programming language) , materials science , raman scattering , argon , hydrogen , thermal , optics , analytical chemistry (journal) , raman spectroscopy , atomic physics , chemistry , physics , organic chemistry , quantum mechanics , chromatography , meteorology , computer science , programming language
Optical signals of gas temperature, species concentration, and electric field are monitored in simple mixtures at room temperature and in the fuel-rich region of a hydrogen diffusion flame. A two-beam pure-rotational coherent anti-Stokes Raman scattering (CARS) approach was utilized for the temperature and species detection, where the combined pump/Stokes pulse doubled as the electric field induced second harmonic generation (EFISHG) pump for the electric field detection. Time-averaged EFISHG signals in environments with argon, nitrogen, oxygen, hydrogen, and air were found to match the relative hyperpolarizabilities of the molecules tabulated in literature. Measurements in a dynamic H 2 -air environment represented the ability to monitor the signal dependence of species on a single-shot basis. Time-averaged EFISHG signals in different thermal environments showed the expected ∝1 T 2 EFISHG signal dependence when also correcting for relative H 2 / N 2 concentrations. Finally, measurements in a flame showed the ability to monitor the EFISHG signal dependence on the gas temperature on a single-shot basis in a plasma discharge environment.