You can find such lasers at price ranges from $10000 to $10000000. Please, I don't guarantee that all 10000 terahertz lasers will be enough, but THAT, is where you come in. Find the correct laser. Please find a good intensity as well. (More intensity, the better.) You can use lenses to increase intensity. I would prefer you to RENT a laser, because it is cheaper. If you want to, you can buy one. Or make one, if you can be sure they won't implode while you do this work.
Also, buy a beam splitter so you can split the laser to go all around the bead in the reaction chamber. That is why it is so powerful. Consistent energy from all sides.