Micro electric fields detection improvements: Steps toward tailoring cold atmospheric pressure plasma

From microfabrication to medicine, agriculture to surface decontamination and many more, applications of cold plasma technology seem limitless. The ability of cold atmospheric pressure plasma to generate highly reactive species through the plasma's electric field is very relevant for plasma tailoring applications. An efficient, sensitive, and high-resolution detection techniques to determine the electric field is needed for time and spatial resolved diagnostics. We proposed to use electric field-induced second harmonic, a well-established nonperturbative technique for measuring the amplitude and orientations of cold atmospheric plasma electric fields. Although E-FISH allows for a good and tunable time resolution, it has been shown that E-FISH presents some issues with spatial resolution and sensitivity. Work on enhancing these two characteristics of E-FISH have been made by our team and collaborators. Using a femtosecond laser, we have developed an amplified E-FISH technique that will allow cross beam measurements for high spatial resolution. The presented results confirmed the improvement of the electric field detection technique, the E-FISH, and will certainly deepen our knowledge on the spatio-temporal electric field distribution of cold atmospheric plasma.