Highly Efficient Resonant Microwave Plasma Jets*

Cold plasma jets are critical in many application fields. However, generating stable plasma jets is not trivial, as energy-hungry machines are often required. This is why most of the current plasma jet sources are bulky and expensive units, as they are inefficient in transferring energy to the plasma. Efficient plasmas with low power consumption impact a wide range of applications such as plasma medicine, food and water decontamination, electric propulsion, and reconfigurable RF electronics.

Due to their ability to store and enhance EM energy, it is possible to employ microwave resonant structures to achieve high-efficiency plasmas with low power consumption. The higher the resonator’s quality factor, the higher the field enhancement. In resonant microwave plasmas (RMPs), electromagnetic energy is concentrated at specific spatial locations within resonant structures, creating favorable conditions for gas breakdown and plasma formation. These RMPs exhibit various advantageous features, including stable discharges, a higher degree of ionization and dissociation, elevated electron density, increased production of reactive species, lower plasma discharge temperatures, and reduced ignition voltage. This talk discusses our recent progress in developing efficient resonant microwave plasma jets and lines based on evanescent-mode cavity resonators [1] and anapole resonators [2].