Quantum information dynamics in multipartite integrable systems

Understand

In a non-equilibrium many-body system, the quantum information dynamics between non-complementary regions is a crucial feature to understand the local relaxation towards statistical ensembles.

• Unfortunately, its characterization is a formidable task, as non-complementary parts are generally in a mixed state.
• We show that for integrable systems, this quantum information dynamics can be quantitatively understood within the quasiparticle picture for the entanglement spreading.
• Precisely, we provide an exact prediction for the time evolution of the logarithmic negativity after a quench.