Entanglement negativity in the harmonic chain out of equilibrium

Understand

We study the entanglement in a chain of harmonic oscillators driven out of equilibrium by preparing the two sides of the system at different temperatures, and subsequently joining them together.

• The steady state is constructed explicitly and the logarithmic negativity is calculated between two adjacent segments of the chain.
• We find that, for low temperatures, the steady-state entanglement is a sum of contributions pertaining to left- and right-moving excitations emitted from the two reservoirs.
• In turn, the steady-state entanglement is a simple average of the Gibbs-state values and thus its scaling can be obtained from conformal field theory.