Reduction of electron losses with voltage prepulse in magnetically insulated transmission lines

We present the impact of a voltage prepulse on initial electron losses in magnetically insulated transmission lines (MITLs). We demonstrate that introducing a modest 74-kV, 60-ns voltage prepulse ahead of the drive voltage in a 10-MA driver can reduce the electron losses inside the MITL by a factor of 50. This, in turn, decreases anode heating caused by these losses by a factor of 180. Finally, we briefly discuss the implications of this technique for the Z machine at Sandia National Laboratories and future high-current drivers.