Abstract

We consider a quantum system in interaction with several thermal baths, and study the energy flux between the system and the baths. The influence of the baths on the system is modeled by adding a dissipative term to the Schrödinger equation, making it a “Lindblad equation”; the dynamic is no more unitary but consists in completely positive trace-preserving maps. Under a detailed balance condition, we can define the energy flux coming from each baths into the system; they satisfy the second principle, and we can for example design a quantum heat pump . I will introduce the formalism of quasi-free fermionic systems, and show that no heat pump can be constructed from such systems. If time permits, I will describe what happens when the fluxes are continuously measured, and how to describe the large deviations of these fluxes, in the spirit of Jaksic Pillet and Westrich