So my first thought is no, that this would not be possible via antenna. The theory I've heard is that once the frequency becomes high enough, the electricity will start to only stay on the surface of the antenna, called a skin effect. Most likely, the antenna would melt before any sub-nuclear particles are emitted.
Now, I'm not discouraging you from going for it, for I could be totally wrong. And that's what breakthroughs are all about right. Doing something previously thought impossible. Not to get controversial, but Tesla did lots of high-frequency research. It's hard to find a lot of information about his experiments though because a lot of his work was burned away.
If the capacitor direction doesn't work remember that there are lots of ways to create high frequency. Just remember that the amount of power it takes to create/separate mass into things like higgs bosons is extremely large. If you have the electrical resources, go for it!
Also make sure you have some kind of safety measure in place. You don't want to get radiation poisoning if you emmit x-rays or something. Good luck!