Energy flux near the junction of two Ising chains at different temperatures
arXiv:1008.5099 · doi:10.1209/0295-5075/91/50003
Abstract
We consider a system in a non-equilibrium steady state by joining two semi-infinite Ising chains coupled to thermal reservoirs with {\em different} temperatures, and . To compute the energy flux from the hot bath through our system into the cold bath, we exploit Glauber heat-bath dynamics to derive an exact equation for the two-spin correlations, which we solve for and arbitrary . We find that, in the sector, the in-flux occurs only at the first spin. In the sector (sites ), the out-flux shows a non-trivial profile: . Far from the junction of the two chains, decays as , where is twice the correlation length of the {\em equilibrium} Ising chain. As , this decay crosses over to a power law () and resembles a "critical" system. Simulations affirm our analytic results.
6 pages, 4 figures, submitted to EPL