Study On Performances And Structure Of Plasma Electrode Electro-optical Switch Of ICF Driver

Largely aperture electric-optics switch that employ plasma as electrodes is one of the key technologies for the development of inertial confinement fusion (ICF) drivers. Its essentiality to the development of ICF driver has been expounded. Its structures and performances have been researched through analysis theoretically or experiments. We have gotten several progresses as follows:1. The structure of plasma electrode Pockels cell (PEPC) has been researched totally through the electrical views for the first time. The basic principles for largely aperture PEPC with thinness crystal plane have been expounded.2. It is the first times to use horniness anodize aluminum film as the isolator of plasma in P.R.China. The life-time and breakdown voltage of anodize aluminum film have been tested. The lowest thickness of film for plasma isolation is optimized to 60μm which is less than Lawrence Livermore National Laboratory's (LLNL's) results(100μm). This results cuts down greatly the difficulties and risks of processing the film.3. We lodged and proved through experiments that the distance between glow discharging electrode and the surface of electric-optic crystal will affect the distribution of plasma density near crystal's surface, and come into affect the voltage of half wave for the first time. It would be good to optimize the structures, to decrease the voltage and future to enhance reliability and stability.4. Physics processes of PEPC's electrical leakage have been analyzed totally. We lodged the concepts that PEPC's electrical leakage include the plasma leakage to ground and high voltage breakdown between the plasma electrode which being high potential and the ground5. We bring forward firstly that to protect the gas from breakdown by increasing the vacuum in the tube, and design a special isolator to solve the problem of electrical leakage totally. It also increases the reliability and the engineering practicability of PEPC.6. To satisfy the demands of building a prototype of SG-III, we designed and built a 240mm by 240mm large aperture optical-switching, its full aperture switching efficiency is higher than 98% and switching speed is less than 95ns.These key parameters are suitable for the requirements of SG-III.It gave the important parameters for future structural designs of new generation ICF drivers.