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The design of an optical current sensor to be used in a pulsed power generator is presented. The current sensor is based on the polarization rotation by the Faraday effect. GEPOPU is a pulsed power generator, 110 kA, 120 ns double transit time, 1.5 Ω coaxial geometry, and current rise time of 50 ns. Two different optical geometries surrounding the conductor were tried, using Amici roof prism and pentaprism to go around the current once, as a way to preserve the state of polarization along the optical path by means of complementary reflections within the sensing element. We believe this to be the first time that such large and rapidly varying currents have been measured with this configuration. The values obtained for both geometries agree with the values obtained with a Rogowski coil. The traces obtained are completely noise-free and no significant time lag has been observed between the current determined from the Faraday rotation and the current measured using a Rogowski coil.

Experimental evidence on the compression of a laser initiated hollow gas embedded z-pinch discharge is presented. The hollow z-pinch is initiated by a laser-produced annular plasma formed on the cathode surface of the pulsed power generator in an ambient atmosphere of 0.3 atm of hydrogen gas. Two different initial radii of R 0 = 2 mm and R 0 = 3 mm of the z-pinches were investigated using schlieren imaging and Mach-Zehnder interferometry. The z-pinches presented hollow electron density profiles with peak values on the order of 10 18 cm −3 and a time average Bennett temperature of 150 eV. Imploding radial velocity of 5 km s −1 is measured. The hollow profile and stability of the plasma column are maintained during the complete observation time. This observation time is approximately ten Alfvén transit time and it is longer than the current peak time.