Development of Solid-State Drivers for the NIF Plasma Electrode Pockels Cell

Large aperture plasma electrode pockels cells (PEPC) are an enabling technology in the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory. The Pockels cell allows the NIF laser to take advantage of multi-pass amplifier architecture, thus reducing costs and physical size of the facility. Each Pockels cell comprises four 40-cm times 40-cm apertures arranged in a 4times1 array. The combination of the Pockels cell and a thin-film polarizer, configured in a 4times1 array, form an optical switch that is key to achieving multi-pass operation. Solid-state Plasma Pulse Generators (PPGs) and high current high voltage solid-state Switch Pulse Generators (SPGs) have been developed for use in the PEPC. The solid-state plasma pulse generators initiate and maintain plasma within the cells; each pulser is capable of delivering 60 J of energy to each plasma channel. Deployment of the solid-state PPGs has been completed in NIF. The MOSFET-switched SPG is capable of delivering a requisite fast rise time, 17 kV flattop pulse to the cells´ nonlinear crystals. A complete software and hardware control system has been developed and is currently being tested for use on the solid-state SPGs. Also a transmission line modeling, development, and testing effort is in process, in support of NIFs´ Advanced Radiographic Capabilities (ARC). Work is scheduled for completion by the end of the calendar year.