Transport in Out-of-Equilibrium XXZ Chains: Exact Profiles of Charges and Currents

Understand

We consider the non-equilibrium time evolution of piecewise homogeneous states in the XXZ spin-1/2 chain, a paradigmatic example of an interacting integrable model.

• The initial state can be thought as the result of joining chains with different global properties.
• Through dephasing, at late times the state becomes locally equivalent to a stationary state which explicitly depends on position and time.
• We propose a kinetic theory of elementary excitations and derive a continuity equation which fully characterizes the thermodynamics of the model.