Piezoelectric Materials for Plasma Generation*

Conventionally, atmospheric pressure plasmas and gas discharges are generated via the application of high voltage – upwards of kilovolts and beyond – to metal electrodes. While such an approach works for laboratory, industrial, and other stationary applications, it is less suited for portable plasma devices that can be taken into field applications, such as disaster areas or developing regions. Non-centrosymmetric crystals, which are crystalline materials where the unit cell does not have a central point of symmetry, offer the potential to convert other forms of energy – such as mechanical or thermal energy – directly into plasma generation, mitigating the need for a high-voltage power supply. Piezoelectric crystals, in particular, can produce significant polarization via electromechanical coupling that lead to surface voltages exceeding the breakdown potential of air and the generation of plasma jets and streamers directly from the piezoelectric surface. This talk will overview research in this area, with a particular focus on piezoelectric transformers to produce piezoelectric direct discharges in air. Fundamental behavior as well as potential applications will be covered, along with possible directions for future research in this area.