Long range trace detection in aqueous aerosol using remote filament-induced breakdown spectroscopy

Remote filament induced breakdown spectroscopy (R-FIBS) is used for probing a cloud of microdroplets where table salt has been dissolved. These microdroplets are a good simulant for aerosols. We demonstrated experimentally that R-FIBS can efficiently be used as a ppm-level sensing technique to remotely retrieve the composition of microdroplets in clouds located at a distance. The technique has been successfully tested up to 70 m and, as revealed by extrapolation, showed great potential for kilometer-range application. The proposed technique is sensitive to the solvent as well. For the first time, to the best of our knowledge, four hydrogen bands from the Balmer series were observed in an aqueous microdroplet cloud after H2O molecules were broken by the light filaments.