Thanks for the explanation. I looked up some of those designs.
Now I'm really puzzled why no one has tried a more naive approach. I'm picturing a hollow metal sphere with a high positive charge with positive ions inside of it. Wouldn't it push them all together and with a high enough charge get them hot enough to fuse?
Counterintuitively, this setup would have zero force inside the sphere. It turns out that being closer to charge on one side of the sphere is always exactly balanced out by the more distant side's greater total charge.
Now I'm really puzzled why no one has tried a more naive approach. I'm picturing a hollow metal sphere with a high positive charge with positive ions inside of it. Wouldn't it push them all together and with a high enough charge get them hot enough to fuse?