Not permanently, at least with anything from Green Ronin. Part of the foundation of the game is that you have the powers that you have, and that the GM gives you power points as you advance.
Now, that said, there are ways to get things like it. One way is to simply make an arrangement with your GM that, when he awards power points to the group for their actions, yours are sourced from whatever you have drained from others. You probably won't get a mechanical advantage from it, since most GMs increase the power of the group more or less in lockstep, but it would fit your theme. Secondly, you could get a Variable power with the descriptor being powers that you've gained from others. You still have to spend points on it, and you're limited to the "pool" of points there, and would have to reallocate them for new powers, but it's not the worst of solutions. Thirdly, players can use Hero Points to pay for Extra Effort, said Hero Points being gained from a Complication like "Power Source - Hero gains powers by absorbing the souls of his enemies and faces prejudice and fear as a result".
You didn't specify a system, but this does hold true for both 2E and 3E.
Of course, you can probably find a 3rd-party sourcebook that allows for such things, but that's outside of the official rules of the game, and I'd argue for simply talking with your GM to see if they're willing to houserule it in.