Exploring Time‐Domain Femtosecond Rotational Coherent Raman Scattering for Diagnostics

Journal of Raman Spectroscopy, vol. 56, pp. 666–672

Abstract

ABSTRACT The diagnostic potential of femtosecond (fs) rotational coherent Raman scattering (RCRS) in the time domain is initially investigated. While RCRS concepts in the spectral domain obtain species selectivity and temperature sensitivity by resolving the spectral shape, mainly reflecting the Boltzmann‐distributed, rotational populations of the Raman‐active molecules present, the current time‐domain fs‐RCRS technique resolves the temporal shape of rotational revival signatures, which are influenced both by the population distributions and centrifugal distortion. Experiments in air and pure nitrogen are reported revealing temperature sensitivity in the recorded fs‐RCRS temporal scans. A theoretical model can predict experimental data with good agreement for temporal scans recorded in air at room temperature and pure nitrogen at 293, 400, and 580 K. Theoretical results show that a dual‐probe configuration could provide temperature sensitivity that increases with increasing temperature, that is, directly opposite to the temperature dependence of the sensitivity in spectrally resolved RCRS, which is essentially flat beyond 1500 K. This result suggests that time‐domain fs‐RCRS could be a useful tool for single‐shot thermometry in reactive flow environments, potentially providing improved sensitivity at high temperatures compared to spectral‐domain RCRS techniques. Another major benefit with the time‐domain fs‐RCRS technique is that it only requires a single fs laser source.

Authors 10

1. Meena Raveesh

   Lund University

   Affiliation as printed

   Division of Combustion Physics, Department of Physics Lund University Lund Sweden

2. Ali Hosseinnia corresponding Aachen Chair of Optical Diagnostics in Energy

   RWTH Aachen University · Lund University

   Affiliation as printed

   Chair of Optical Diagnostics in Energy, Process and Chemical Engineering RWTH Aachen University Aachen Germany

   Division of Combustion Physics, Department of Physics Lund University Lund Sweden

3. Abhijit Padhiary

   University of Edinburgh

   Affiliation as printed

   School of Engineering, Institute of Multiscale Thermofluids The University of Edinburgh Edinburgh Scotland UK

4. Xiangyu Wei

   University of Edinburgh

   Affiliation as printed

   School of Engineering, Institute of Multiscale Thermofluids The University of Edinburgh Edinburgh Scotland UK

5. Vassily Kornienko

   Lund University

   Affiliation as printed

   Division of Combustion Physics, Department of Physics Lund University Lund Sweden

6. Elias Kristensson

   Lund University

   Affiliation as printed

   Division of Combustion Physics, Department of Physics Lund University Lund Sweden

7. Andreas Ehn

   Lund University

   Affiliation as printed

   Division of Combustion Physics, Department of Physics Lund University Lund Sweden

8. Brian Peterson

   University of Edinburgh

   Affiliation as printed

   School of Engineering, Institute of Multiscale Thermofluids The University of Edinburgh Edinburgh Scotland UK

9. Mark Linne

   University of Edinburgh

   Affiliation as printed

   School of Engineering, Institute of Multiscale Thermofluids The University of Edinburgh Edinburgh Scotland UK

10. Joakim Bood

    Lund University

    Affiliation as printed

    Division of Combustion Physics, Department of Physics Lund University Lund Sweden