Sure can! I do it all the time so that I have 200-300g portions ready to go.
Cooked chicken will last in a freezer anywhere from 4-6 months. I'd play it safe and eat before 3 months though. Couple of things;
1) Put the chook in the freezer as soon as its cooked - in other words, dont leave it on the kitchen sink for half an hour before you freeze it.
2) Once you have thawed your portion - do not refreeze it! Either eat it or throw it away.