Collective operations can extremely reduce work fluctuations

摘要: We consider work extraction from N copies of a quantum system. When the same work-extraction process is implemented on each copy, relative size fluctuations expected to decay as 1/\sqrt{N}. Here, we protocols where can be processed collectively, and show that in this case disappear exponentially fast N. As consequence, considerable proportion average extractable W obtained almost deterministically by globally processing few state. This derived two canonical scenarios for extraction: (i)~in thermally isolated systems, corresponds energy difference between initial passive states, known ergotropy, (ii)~in presence thermal bath, given free states.a#13;