Statistical mechanics of entanglement mediated by a thermal reservoir I

TL;DR

This paper investigates how two defect particles coupled to a harmonic chain can become entangled through a thermal reservoir, especially at low temperatures and with specific initial states, providing a microscopic understanding of bath-induced entanglement.

Contribution

It offers a microscopic model and numerical analysis demonstrating entanglement generation between defects mediated by a thermal chain reservoir, even without direct interaction.

Findings

Entanglement occurs at low temperatures when defects are prepared in squeezed states.

Numerical simulations identify parameter regimes for entanglement.

Bath-induced entanglement can be observed in this microscopic setting.

Abstract

Two defect particles that couple to a harmonic chain, acting as common reservoir, can become entangled even when the two defects do not directly interact and the harmonic chain is effectively a thermal reservoir for each individual defect. This dynamics is encountered for sufficiently low temperatures of the chain and depends on the initial state of the two oscillators. In particular, when each defect is prepared in a squeezed state, entanglement can be found at time scales at which the steady state of a single defect is reached. We provide a microscopic description of the coupled quantum dynamics of chain and defects. By means of numerical simulations, we explore the parameter regimes for which entanglement is found under the specific assumption that both particles couple to the same ion of the chain. This model provides the microscopic setting where bath-induced entanglement can be observed.