Seminário de Computação e Informação Quântica 

21/04/2015, 10:00 — 11:00 — Sala P3.10, Pavilhão de Matemática
Mauro Paternostro, Queen's University Belfast

On Landauer principle for non-equilibrium quantum systems

Using the operational framework of completely positive, trace preserving operations and thermodynamic fluctuation relations, I will derive a lower bound for the heat exchange in a Landauer erasure process on a quantum system. The bound comes from a non-phenomenological derivation of the Landauer principle which holds for generic non-equilibrium dynamics. Furthermore the bound depends on the non-unitality of dynamics, giving it a physical significance that differs from other derivations. I will illustrate the framework to the model of a spin-1/2 system coupled to an interacting spin chain at finite temperature.

I will further investigate the link between information and thermodynamics embodied by Landauer principle in an open-system dynamics embodied by a collision-based mechanism involving a suitable multipartite system and a multi-particle spin reservoir at finite temperature. I will demonstrate that Landauer principle holds, in such an open configuration, in a form that involves the flow of heat dissipated into the environment and the rate of change of the entropy of the system, Quite remarkably, such a principle for heat and entropy power can be explicitly linked to the rate of creation of correlations among the elements of the multipartite system and, in turn, the non-Markovian nature of their reduced evolution. I will illustrate such principle using two paradigmatic cases.