Louis Saugé defended his PhD "Étude expérimentale sur les jets de plasma à pression atmosphérique : champs électriques, mécanismes de décharge et effets biologiques"

Congratulations to Louis Saugé who successfully defended his PhD "Étude expérimentale sur les jets de plasma à pression atmosphérique : champs électriques, mécanismes de décharge et effets biologiques" on November 27, 2025.

Summary : 
Atmospheric pressure plasma jets (APPJs) are attracting growing interest due to their multiple applications, particularly in the biomedical field. In wound healing, most research in plasma medicine attributes their positive effects on biological targets to reactive oxygen and nitrogen species (RONS) and overlooks other plasma components such as UV radiation, metastable species, or electric fields. The aim of this thesis is to demonstrate the importance of studying the electric fields emitted by the plasma in order to better understand the physics of the associated discharges. Few studies in the literature compare different experimental devices in terms of electrode configuration or reactor geometry. This study examines and compare several configurations by using different high voltage sources (pulsed DC or kHz AC) as well as different reactor geometries (linear reactor, diffusive reactor) and electrode configurations (pin, pin-ring, ring, ring-ring). To do this, several diagnostics are used, including the Pockels effect electric field probe, and intensified high speed camera. These different configurations are then studied when the plasmas interact or not with a dielectric target, before studying the quantities of species transferred to aqueous targets. Finally, the biological impact associated with these configurations is compared, highlighting that electric fields are an essential component in the wound healing process.