For symmetric encryption quantum computing doesn't do much. It reduces the running time of brute-force search by sqrt. So in 2^128 operations you could brute force a 2^256 big search space (i.e. a 256 bit key).
That's why many symmetric systems have moved to a 256 bit key. It makes them quantum safe because 2^128 operations are considered impossible. (According to some physicsists it is guaranteed to boil the oceans).
You might be looking for quantum computing. They're right down the hall, second door on the left.