Changing the heat conductivity: an analytical study.

We address the problem of controlling the energy flow in lattice systems: we investigate, in an analytical approach, the properties of the heat conductivity of the harmonic crystal with self-consistent stochastic reservoirs, a single model with normal conductivity. For the case of weak interparticle interaction, in a perturbative analysis, we obtain an expression for the thermal conductivity and show how to decrease and/or increase the heat current inside the system by changing the masses of the particles and/or the on-site potentials. These results may be useful in the construction of devices controlling the heat conduction.