Investigation of sub-nanosecond breakdown through experimental and computational methods
Chaparro, Jordan E.
MetadataShow full item record
Sub-nanosecond breakdown, at sub-atmospheric pressures, is governed by significantly different physics when compared to standard breakdown processes. Applied field risetimes of 100s of ps combined with high peak amplitudes and short gap spacing allows for overvoltage to develop in the gap greatly exceeding static breakdown conditions. These conditions lead to a significant portion of electrons in the runaway mode and highly inhomogeneous charge distributions that greatly affect the scaling relationships for the discharge. The continued progression of pulsed power applications to shorter time scales makes a full understanding of such discharges necessary for the future development of devices relying on ultrafast, high voltage pulses. Insights into the physical background of sub-nanosecond breakdown are provided in this dissertation through both empirical analysis and numerical modeling. The modeling of the discharge is implemented through a customized particle-in-cell code combined with Monte-Carlo methods for simulating particle collisions. The results of the model show reasonable agreement to experimental results across the full range of test parameters. Additional insights into physical mechanisms that are not easily empirically measured are provided.