Characterization of flow-induced turbulence in a cold micro-plasma jet

Atmospheric pressure plasmas are ‘non-equilibrium’ plasmas that exhibit wide difference in electron (Te~0.5-1 eV) and ion (Ti~0.025 eV) temperatures. These plasmas, generated inexpensively as plasma jets at room temperature and atmospheric pressure, directly engage with ambient air, hence contain reactive oxygen and nitrogen species (RONS). The lower gas temperature and presence of RONS in plasma jets make them suitable for diverse applications, especially in biomedicine [1]. The concentration of RONS is crucial in biological sample treatment, serving as the plasma dosage for targeted cells or tissues. Flowinduced turbulence in plasma jets can disrupt the distribution of energy and particles, consequently affecting the concentration of RONS. In our earlier work, enhanced floating potential fluctuations have been observed during the turbulent mode of the plasma jet which might further impact RONS production, as the RONS evolution timescales (~0.5-1 ms) are comparable with the plasma floating potential fluctuation timescale (~0.1-1 ms) [2, 3].