Transient measurement of the discharge termination field in an atmospheric pressure pulse discharge based on electric field induced second harmonic generation

Abstract Motivated by the need for precise control of plasma parameters of atmospheric non-equilibrium plasma, we present an approach for the transient measurement of the electric field for discharge termination (i.e., the discharge termination fields, DTFs) based on the electric field induced second harmonic generation (E-FISH) method. This approach utilizes a custom-designed electrode structure and introduces the integration system as the connection between the electric field and the response signals according to the superposition theorem of electric fields. Considering the electric field profile, the effect of the undesired electric field outside the copper foils on second harmonic generation is eliminated, leading to more accurate DTF measurement results. The DTF for positive discharges decreases with increasing voltage amplitude or gap height, while the DTF for negative discharges displays the opposite trend, both of which are closely related to the discharge magnitude. Moreover, the higher measurement accuracy of the proposed method is further demonstrated in the experimental measurement of electric field evolution. The presented quantitative measurements can be used to validate high-fidelity modeling predictions and facilitate a deeper understanding of the physical mechanisms of discharge extinction.