PROJECT TITLE :

Ferroelectric crystals for the low-voltage operation of surface dielectric barrier discharges

ABSTRACT:

Dielectric barrier discharges (DBD) are commonly used to generate surface plasmas in atmospheric conditions due to their broad operational scope. Yet, high input voltages are typically required to breakdown atmospheric air. Ferroelectric crystals, however, can be used in place of dielectrics in order to reduce the driving voltage required to generate a DBD. Ferroelectrics are unique in that they have spontaneous polarizations that can be reversed by an applied electric field and also typically have very large relative permittivities. By using a ferroelectric with a large permittivity and small coercive fields, the applied voltage required to generate a discharge was reduced to <600 V in atmospheric air, and a visible glow and current filaments consistent with polarization switching were observed. Analysis of the discharge showed that the onset voltage follows a power law relation with its capacitance. Furthermore, poling the ferroelectric with a large DC voltage before use also reduced the onset voltage of the discharge.