Reply To: Great News!

[asymmetric_implosion]

andrewmdodson wrote: http://www.evincetechnology.com/tech_overview.html

possibility of diamond switches evolving soon into something useful for the focus fusion project?

The website is very vague. My comment on using field emission electron sources is the limited current in the trigger. One should note that diamond is not a tickle trigger like Si. It usually takes a substantial trigger to turn diamond on and the trigger needs to stay on to keep the switch conducting due to the short carrier lifetime (~1ns). Laser triggered diamond switches have this problem as the necessary laser intensity is difficult to maintain for more than a few ns. It seems they are targeting power grids which is a very different beast than pulse power. I know diamond has come a long way due to work by groups like Diamond Detectors Limited, but the trigger is still the weakness. This is the reason diamond is a radiation detector right now. Last I checked and it has been a while, these type of switches are limited to ~1 kA. Going to a 3 MA system will take many components in parallel. The missing piece is the voltage hold off. Ideally, you do not want to have switches in series. Switches in parallel are not a much of a problem. The switch is going to have to hold ~60 kV. Again, it’s been a while but diamond has been tested successfully to 50 kV in photo conducting configurations.