Nonradiating Resonances: Anapoles Enabling Highly Efficient Plasma Jets Within Dielectric Structures

Plasma plays a pivotal role in numerous applications. When plasma interacts with air, it creates rare and highly reactive species. Typically, the generation of atmospheric air plasma jets relies on resonant cavities to enhance plasma efficiency. In this study, we have harnessed the innovative concept of nonradiating sources, known as anapoles, which utilize the lowest order multipoles—specifically, electric-electric dipole interactions—within a hybrid metallodielectric structure. This approach enhances the near electric field, facilitating gas breakdown for the realization of a plasma jet. The achievement of a dielectric plasma jet is remarkable in its own right, particularly when considering the open structure employed, which enables frequency tuning. Furthermore, the demonstrated prototype surpasses the existing plasma jets in several key aspects, including compactness, compatibility with planar fabrication techniques, power efficiency, cost-effectiveness, tunability, and electron density. With these substantial enhancements, the proposed technique can substantially enhance plasma jet technology and open exciting avenues for exploring novel applications.