Topological effects in quantum thermodynamics

The thermodynamics of open quantum systems coupled to topological fields is analyzed. Both the Aharonov-Bohm effect for systems of charged particles and the Aharonov-Casher effect for systems of neutral spin-1/2 particles are considered, and a general definition for the flux of a physical observable is proposed. A proper treatment of the work done by the topological fields is necessary to ensure that the entropy of the system is a state function, and to avoid certain thermodynamic paradoxes. In particular, the flux of entropy in the system induced by the topological fields naively appears to diverge as the temperature approaches absolute zero, in violation of the 3rd law of thermodynamics.