We report on the development and application of coherent Rayleigh-Brillouin scattering for the in situ detection of large molecules and nanoparticles. This four wave mixing diagnostic technique relies on the creation of an electrostrictive optical lattice in a medium due to the interaction between polarized particles and the intense electric field gradient created by the optical interference of two intense pulsed laser beams. Though this interaction, we can detect the temperature, pressure, relative density, polarizability and speed of sound of a gas and gas mixture. This diagnostic was already successfully demonstrated in atomic and molecular gaseous environments, where the different gas polarizabilities and pressures were successfully measured. We are currently conducting in situ measurements with large molecules and nanoparticles produced in an arc discharge, the results of which will be presented in this meeting.
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