Ferroelectric Thick Film in an Insulator of a Low-Energy Plasma Focus

The electric breakdown along the insulator in a plasma focus (PF) device is fundamental for the formation of a homogeneous and symmetric current sheath. From this point of view, the primary electron emission is essential to set the appropriate initial conditions. In this paper, the authors study the effect and viability of an unpolarized ferroelectric lead germanate Pb₅Ge₃O₁₁ thick film covering the alumina insulator of a 400-J Mather-type PF device on the plasma formation and evolution during the discharge in the PF mode. For over several hundreds of electrical discharges, different insulators covered with the lead-germanate films showed a good mechanical and electric performance. The electrical diagnostic signals are highly reproducible, shot to shot, with a clear definition of the plasma pinch on the axis of discharge