Ultrafast co-axial Marx generator delivering 800ps risetime high voltage pulse for vacuum breakdown studies

A Marx generator delivers high power electrical pulse in very short duration and can be configured to be compact. This ultrafast coaxial Marx generator has also been developed without pulse shaping/peaking circuit. The results of 5-stage ultrafast coaxial Marx generator has a rise time of 800ps, maximum output voltage 75kv, pulse width(FWHM) of 1.5ns, and source impedance 63Ω is presented. The coaxial geometry is used throughout the system to achieve low value of inductance leading to fast rise time of the output pulse. The fast Marx generator, load impedance and Current Viewing Resistor (CVR) are connected in series and the 50mΩ CVR is used as a diagnostics to measure the output current. This compact fast Marx generator is fit into a stainless steel (metallic) cylinder. The fast Marx generator is tested for the charging voltages of 10kv with 50Ω and 100Ω ceramic resistive loads. The design and experimental results of coaxial fast Marx generator are discussed.