I considered this route some years ago and even picked up a 50 kV, 0.1 mFd capacitor (rather large, oil filled affair to say the least.) I, of course, have bottled D2, two excellent high vacuums (a turbo and DP) and three very high voltage supply systems (a pulsed 65 kV voltage multiplier system of my own design, a moderate current Glassman: 10 ma 40 kV supply; and my fusor's very high current 30 kV supply (on loan).)
However, as I learned the hard way, neutron detection is a big issue.
After finally putting together a working BF3 system and getting neutrons (yeah!) issues quickly over took my efforts; sadly, an over voltage damaged the system so, once again, I am struggling to put a working system together. The issue of neutron detection had side tracked me for years prior to my recent success so I am extremely unhappy about the new events... . As such, I am debating whether to continue that research idea relative to plasma self focus.
After reading this post, I am not sure the approach is worth the effort if a std detector isn't gonna cut it! That is not something I had considered. I was in the process of building a scintillation detector (have the neutron sensitive plastic, HV photo-detector tube, special power supply and now just need to assemble all that and hook it up to a counter. ) I was planning to check the new detector with my current fusor. But if that class of detector won't work with a focus system I have to abandon that project for certain. I will not use activation (don't trust it) and am not buying a bubble detector now after all I've invested in regular detectors ... .