Heat Transport in spin chains

Carlos Mejía-Monasterio, Hannu Christian Wichterich

Pascal Fries, Haye Hinrichsen B

Abstract We study the dynamics of an initially thermalized spin chain in the quantum XY-model, after sudden coupling to a heat bath of lower temperature at one end of the chain. In the semi-classical limit we see an exponential decay of the system-bath heatflux by exact solution of the reduced dynamics. In the full quantum description however, we numerically find the heatflux to reach intermediate plateaus where it is approximately constant—a phenomenon that we attribute to the finite speed of heat transport via spin waves.

Sonja Fischer, Lars Fritz

Jinshan Wu, Mona Berciu

We investigate heat transport in various quantum spin chains using the Redfield equation. We find that anomalous heat transport is linked not to the integrability of the Hamiltonian, but to whether it can be mapped to a model of noninteracting fermions. Our results also suggest how seemingly anomalous transport may occur at low temperatures in a much wider class of models.

Yonghong Yan, Qifeng Liang, Hui Zhao

Juan José Mendoza-Arenas, Sarah Al-Assam, Stephen R. L. Clark +1 more

In this work we study the heat transport in an XXZ spin-1/2 Heisenberg chain with homogeneous magnetic field, incoherently driven out of equilibrium by reservoirs at the boundaries. We focus on the effect of bulk dephasing (energy-dissipative) processes in different parameter regimes of the system. The non-equilibrium steady state of the chain is obtained by simulating its evolution under the corresponding Lindblad master equation, using the time evolving block decimation method. In the absence of dephasing, the heat transport is ballistic for weak interactions, while being diffusive in the strongly-interacting regime, as evidenced by the heat-current scaling with the system size. When bulk dephasing takes place in the system, diffusive transport is induced in the weakly-interacting regime, with the heat current monotonically decreasing with the dephasing rate. In contrast, in the strongly-interacting regime, the heat current can be significantly enhanced by dephasing for systems of small size.