This is something akin to maxwell's demon. All Quantum processes save for measurement are reversible, and as such many thermodynamics concepts don't apply or don't apply in all circumstances.
It's worth noting that the measurement thing is what binds us to entropy's cold embrace in the long run. There's no maxwell's demon type thing that could run indefinitely without eventually having to perform something non-reversable, unless there's some horrible hack we haven't thought of yet.
