Anti matter is the fundamental purest and most effective form of energy that is concievable to us at this time. A hydrogen bomb is only 2% effective, antimatter is 100%. A tablespoon of antimatter could take a ship to the moon and back. This is one of the most important aspects of science today. Matter is not destroyed and with nanotechnology a interstellar craft could conceivably have a 100% recycling rate but still to perform the actions to recycle that material and to keep the ship moving and powered a powerful form of energy would be needed.

I dont think this is out of reach but it's not going to be something you see in a year or two either. A vast effort taking the resources of a nation was invested into developing nuclear technology. It will take at least that much effort to do the same with antimatter on a production scale to be effective.