Diffusion and entanglement in open quantum systems

The macroscopic fluctuation theory provides a complete hydrodynamic description of nonequilibrium classical diffusive systems. As a first step towards a diffusive theory of open quantum systems, we propose a microscopic open quantum system model - the selective dephasing model. It exhibits genuine quantum diffusive scaling. Namely, the dynamics is diffusive and the density matrix remains entangled at large length scales and long time scales.