Extensive Long-Range Entanglement in a Nonequilibrium Steady State

Understand

Entanglement measures constitute powerful tools in the quantitative description of quantum many-body systems out of equilibrium.

• We study entanglement in the current-carrying steady state of a paradigmatic one-dimensional model of noninteracting fermions at zero temperature in the presence of a scatterer.
• We show that disjoint intervals located on opposite sides of the scatterer, and within similar distances from it, maintain volume-law entanglement regardless of their separation, as measured by their fermionic negativity and coherent information.
• The mutual information of the intervals, which quantifies the total correlations between them, follows a similar scaling.