Effects of one-way correlations on thermodynamics of a multipartite open quantum system

In this study we investigate how correlations of a multipartite quantum system affect its thermodynamics when subsystems of which interact with a thermal reservoir in a cascaded manner. We propose the concept of apparent temperature for an individual subsystem, which is determined by one-way correlations of the subsystem with its preceding subsystems and governs the direction of heat flow between the subsystem and reservoir. We demonstrate the possibility of reversing heat flow between the subsystem and reservoir conditioned on the apparent temperature and derive the conditions for achieving this reversal. We also examine the entropy production of this thermodynamic process and observe a tradeoff between contributions from one-way and global correlations to entropy production. Our results provide insight into the roles of one-way multipartite correlations on thermodynamic properties and expand the ways of applications of quantum resources in the area of thermodynamics.