Feasibility study on various optics design for X-pinch high voltage measurement system using the Pockels electro-optic effect

We develop an optics-based high voltage sensor applicable to X-pinch plasma source using a Pockels cell which changes the refractive index according to the intensity of externally applied electric fields. The developed voltage sensor has a nsec temporal resolution allowing us to follow dynamics of X-pinch plasmas. In addition, since the sensor works as a polarimetry, it makes no electrical contacts with the X-pinch system where a high voltage (\textasciitilde 100 kV) with the fast rising (\textasciitilde nsec) time is applied. Various optics configurations for the sensor are designed and examined on the X-pinch system without plasmas by applying a voltage up to a few tens of kV with a rising time of \textasciitilde 10 nsec. We present the investigated optics configurations and discuss their performance.