Using a gas inside the inner tube and a different inductance could yield a much higher out-put. If you take into consideration most of the research on the market. I can certainly see that you’ll need the beryllium, but the Boron would be the thing I would be least likely to like in the equation. To quote wikipedia:
Boron is never found as a free element in nature.
With this you also have to have enough Boron around in order to make the proper substances to make this gasouse stuff inside the tube as well. With all of this in mind you can just look and see that you are able to see how it can be done though at the same time there are those setbacks that can befall a Defense Contractor in this long process of getting approval for everything. It’s not simple to get clearnce levels and then work on stuff and then acquire materials for small testing and then the actual construction of a larger scale device for “show-and-tell” then you go from there. This is a very long process that just got back underway with senate support in the last few yrs.